diff --git a/openslides/agenda/models.py b/openslides/agenda/models.py
index 48e26a021..b0476273e 100644
--- a/openslides/agenda/models.py
+++ b/openslides/agenda/models.py
@@ -17,6 +17,10 @@ from openslides.utils.utils import to_roman
 
 
 class ItemManager(models.Manager):
+    """
+    Customized model manager with special methods for agenda tree and
+    numbering.
+    """
     def get_only_agenda_items(self, queryset=None):
         """
         Generator, which yields only agenda items. Skips hidden items.
@@ -36,14 +40,14 @@ class ItemManager(models.Manager):
                 yield from yield_items(item_children[item.pk])
         yield from yield_items(root_items)
 
-    def get_root_and_children(self, queryset=None, only_agenda_items=False):
+    def get_root_and_children(self, only_agenda_items=False):
         """
         Returns a list with all root items and a dictonary where the key is an
         item pk and the value is a list with all children of the item.
-        """
-        if queryset is None:
-            queryset = self.order_by('weight')
 
+        If only_agenda_items is True, the tree hides HIDDEN_ITEM.
+        """
+        queryset = self.order_by('weight')
         item_children = defaultdict(list)
         root_items = []
         for item in queryset:
@@ -62,7 +66,7 @@ class ItemManager(models.Manager):
         and children, where id is the id of one agenda item and children is a
         generator that yields dictonaries like the one discribed.
 
-        If only_agenda_items is True, the tree hides ORGANIZATIONAL_ITEMs.
+        If only_agenda_items is True, the tree hides HIDDEN_ITEM.
 
         If include_content is True, the yielded dictonaries have no key 'id'
         but a key 'item' with the entire object.
@@ -121,6 +125,26 @@ class ItemManager(models.Manager):
                 db_item.weight = weight
                 db_item.save()
 
+    @transaction.atomic
+    def number_all(self, numeral_system='arabic'):
+        """
+        Auto numbering of the agenda according to the numeral_system. Manually
+        added item numbers will be overwritten.
+        """
+        def walk_tree(tree, number=None):
+            for index, tree_element in enumerate(tree):
+                if numeral_system == 'roman' and number is None:
+                    item_number = to_roman(index + 1)
+                else:
+                    item_number = str(index + 1)
+                    if number is not None:
+                        item_number = '.'.join((number, item_number))
+                tree_element['item'].item_number = item_number
+                tree_element['item'].save()
+                walk_tree(tree_element['children'], item_number)
+
+        walk_tree(self.get_tree(only_agenda_items=True, include_content=True))
+
 
 class Item(RESTModelMixin, models.Model):
     """
@@ -263,34 +287,6 @@ class Item(RESTModelMixin, models.Model):
                 item_no = str(self.item_number)
         return item_no
 
-    def calc_item_no(self):
-        """
-        Returns the number of this agenda item.
-        """
-        if self.type == self.AGENDA_ITEM:
-            if self.parent is None:
-                sibling_no = self.sibling_no()
-                if config['agenda_numeral_system'] == 'arabic':
-                    return str(sibling_no)
-                else:  # config['agenda_numeral_system'] == 'roman'
-                    return to_roman(sibling_no)
-            else:
-                return '%s.%s' % (self.parent.calc_item_no(), self.sibling_no())
-        else:
-            return ''
-
-    def sibling_no(self):
-        """
-        Counts how many AGENDA_ITEMS with the same parent (siblings) have a
-        smaller weight then this item.
-
-        Returns this number + 1 or 0 when self is not an AGENDA_ITEM.
-        """
-        return Item.objects.filter(
-            parent=self.parent,
-            type=self.AGENDA_ITEM,
-            weight__lte=self.weight).count()
-
 
 class SpeakerManager(models.Manager):
     """
diff --git a/openslides/agenda/static/js/agenda/site.js b/openslides/agenda/static/js/agenda/site.js
index 86919c2fe..621461d58 100644
--- a/openslides/agenda/static/js/agenda/site.js
+++ b/openslides/agenda/static/js/agenda/site.js
@@ -217,6 +217,10 @@ angular.module('OpenSlidesApp.agenda.site', ['OpenSlidesApp.agenda'])
             };
             return typeof _.findKey(projector.elements, predicate) === 'string';
         };
+        // auto numbering of agenda items
+        $scope.autoNumbering = function() {
+            $http.post('/rest/agenda/item/numbering/', {});
+        };
     }
 ])
 
diff --git a/openslides/agenda/static/templates/agenda/item-list.html b/openslides/agenda/static/templates/agenda/item-list.html
index c85b0b6fd..1f306636a 100644
--- a/openslides/agenda/static/templates/agenda/item-list.html
+++ b/openslides/agenda/static/templates/agenda/item-list.html
@@ -44,6 +44,13 @@
           <i class="fa fa-video-camera"></i>
           <translate>Project agenda</translate>
         </a>
+        <!-- auto numbering button -->
+        <a ng-show="!isDeleteMode" os-perms="core.can_manage_projector"
+            class="btn btn-default btn-sm form-control"
+            ng-click="autoNumbering()">
+          <i class="fa fa-list-ol"></i>
+          <translate>Number agenda items</translate>
+        </a>
         <!-- delete button -->
         <a ng-show="isDeleteMode && (items|filter:{selected:true}).length > 0"
             os-perms="agenda.can_manage" ng-click="delete()"
diff --git a/openslides/agenda/views.py b/openslides/agenda/views.py
index 7b3b7c000..2202ae970 100644
--- a/openslides/agenda/views.py
+++ b/openslides/agenda/views.py
@@ -5,6 +5,7 @@ from django.utils.translation import ugettext as _
 from django.utils.translation import ugettext_lazy
 from reportlab.platypus import Paragraph
 
+from openslides.core.config import config
 from openslides.utils.exceptions import OpenSlidesError
 from openslides.utils.pdf import stylesheet
 from openslides.utils.rest_api import (
@@ -47,7 +48,7 @@ class ItemViewSet(ListModelMixin, RetrieveModelMixin, UpdateModelMixin, GenericV
             result = (self.request.user.has_perm('agenda.can_see') and
                       self.request.user.has_perm('agenda.can_see_hidden_items') and
                       self.request.user.has_perm('agenda.can_manage'))
-        elif self.action == 'speak':
+        elif self.action in ('speak', 'numbering'):
             result = (self.request.user.has_perm('agenda.can_see') and
                       self.request.user.has_perm('agenda.can_manage'))
         else:
@@ -219,6 +220,15 @@ class ItemViewSet(ListModelMixin, RetrieveModelMixin, UpdateModelMixin, GenericV
             response = Response(Item.objects.get_tree())
         return response
 
+    @list_route(methods=['post'])
+    def numbering(self, request):
+        """
+        Auto numbering of the agenda according to the config. Manually added
+        item numbers will be overwritten.
+        """
+        Item.objects.number_all(numeral_system=config['agenda_numeral_system'])
+        return Response({'detail': _('The agenda has been numbered.')})
+
 
 # Views to generate PDFs
 
diff --git a/tests/integration/agenda/test_viewsets.py b/tests/integration/agenda/test_viewsets.py
index 9cfda9c83..c82bec1b1 100644
--- a/tests/integration/agenda/test_viewsets.py
+++ b/tests/integration/agenda/test_viewsets.py
@@ -2,7 +2,7 @@ from django.contrib.auth import get_user_model
 from django.core.urlresolvers import reverse
 from rest_framework.test import APIClient
 
-from openslides.agenda.models import Speaker
+from openslides.agenda.models import Item, Speaker
 from openslides.core.config import config
 from openslides.core.models import CustomSlide, Projector
 from openslides.utils.test import TestCase
@@ -233,3 +233,53 @@ class Speak(TestCase):
         else:
             success = False
         self.assertTrue(success)
+
+
+class Numbering(TestCase):
+    """
+    Tests view to number the agenda
+    """
+    def setUp(self):
+        self.client = APIClient()
+        self.client.login(username='admin', password='admin')
+        self.item_1 = CustomSlide.objects.create(title='test_title_thuha8eef7ohXar3eech').agenda_item
+        self.item_2 = CustomSlide.objects.create(title='test_title_eisah7thuxa1eingaeLo').agenda_item
+        self.item_2.weight = 2
+        self.item_2.save()
+        self.item_2_1 = CustomSlide.objects.create(title='test_title_Qui0audoaz5gie1phish').agenda_item
+        self.item_2_1.parent = self.item_2
+        self.item_2_1.save()
+        self.item_3 = CustomSlide.objects.create(title='test_title_ah7tphisheineisgaeLo').agenda_item
+        self.item_3.weight = 3
+        self.item_3.save()
+
+    def test_numbering(self):
+        response = self.client.post(reverse('item-numbering'))
+        self.assertEqual(response.status_code, 200)
+        self.assertEqual(Item.objects.get(pk=self.item_1.pk).item_number, '1')
+        self.assertEqual(Item.objects.get(pk=self.item_2.pk).item_number, '2')
+        self.assertEqual(Item.objects.get(pk=self.item_2_1.pk).item_number, '2.1')
+        self.assertEqual(Item.objects.get(pk=self.item_3.pk).item_number, '3')
+
+    def test_roman_numbering(self):
+        config['agenda_numeral_system'] = 'roman'
+
+        response = self.client.post(reverse('item-numbering'))
+
+        self.assertEqual(response.status_code, 200)
+        self.assertEqual(Item.objects.get(pk=self.item_1.pk).item_number, 'I')
+        self.assertEqual(Item.objects.get(pk=self.item_2.pk).item_number, 'II')
+        self.assertEqual(Item.objects.get(pk=self.item_2_1.pk).item_number, 'II.1')
+        self.assertEqual(Item.objects.get(pk=self.item_3.pk).item_number, 'III')
+
+    def test_with_hidden_item(self):
+        self.item_2.type = Item.HIDDEN_ITEM
+        self.item_2.save()
+
+        response = self.client.post(reverse('item-numbering'))
+
+        self.assertEqual(response.status_code, 200)
+        self.assertEqual(Item.objects.get(pk=self.item_1.pk).item_number, '1')
+        self.assertEqual(Item.objects.get(pk=self.item_2.pk).item_number, '')
+        self.assertEqual(Item.objects.get(pk=self.item_2_1.pk).item_number, '')
+        self.assertEqual(Item.objects.get(pk=self.item_3.pk).item_number, '2')