diff --git a/addons/web/static/src/js/views/calendar/calendar_controller.js b/addons/web/static/src/js/views/calendar/calendar_controller.js
index a6dec31afe1..0c681209825 100644
--- a/addons/web/static/src/js/views/calendar/calendar_controller.js
+++ b/addons/web/static/src/js/views/calendar/calendar_controller.js
@@ -55,6 +55,7 @@ var CalendarController = AbstractController.extend({
         this.readonlyFormViewId = params.readonlyFormViewId;
         this.mapping = params.mapping;
         this.context = params.context;
+        this.previousOpen = null;
         // The quickCreating attribute ensures that we don't do several create
         this.quickCreating = false;
     },
@@ -271,7 +272,8 @@ var CalendarController = AbstractController.extend({
             title += ': ' + this.renderer.arch.attrs.string;
         }
         if (this.eventOpenPopup) {
-            new dialogs.FormViewDialog(self, {
+            if (this.previousOpen) { this.previousOpen.close(); }
+            this.previousOpen = new dialogs.FormViewDialog(self, {
                 res_model: this.modelName,
                 context: context,
                 title: title,
@@ -283,7 +285,8 @@ var CalendarController = AbstractController.extend({
                     }
                     self.reload();
                 },
-            }).open();
+            });
+            this.previousOpen.open();
         } else {
             this.do_action({
                 type: 'ir.actions.act_window',
diff --git a/addons/web/static/tests/views/calendar_tests.js b/addons/web/static/tests/views/calendar_tests.js
index 9ff8474e39d..cc1cc2aeb6a 100644
--- a/addons/web/static/tests/views/calendar_tests.js
+++ b/addons/web/static/tests/views/calendar_tests.js
@@ -5,6 +5,7 @@ var AbstractStorageService = require('web.AbstractStorageService');
 var CalendarView = require('web.CalendarView');
 var CalendarRenderer = require('web.CalendarRenderer');
 var Dialog = require('web.Dialog');
+var ViewDialogs = require('web.view_dialogs');
 var fieldUtils = require('web.field_utils');
 var mixins = require('web.mixins');
 var RamStorage = require('web.RamStorage');
@@ -465,6 +466,62 @@ QUnit.module('Views', {
         calendar.destroy();
     });
 
+    QUnit.test('open multiple event form at the same time', function (assert) {
+        assert.expect(2);
+
+        var def = $.Deferred();
+        var counter = 0;
+        testUtils.mock.patch(ViewDialogs.FormViewDialog, {
+            open: function () {
+                counter++;
+                this.options = _.omit(this.options, 'fields_view');  // force loadFieldView
+                return this._super.apply(this, arguments);
+            },
+            loadFieldView: function () {
+                var self = this;
+                var args = arguments;
+                var _super = this._super;
+                return def.then(function () {
+                    return _super.apply(self, args);
+                });
+            },
+        });
+
+        var event = $.Event();
+        var calendar = createView({
+            View: CalendarView,
+            model: 'event',
+            data: this.data,
+            arch:
+            '<calendar class="o_calendar_test" '+
+                'string="Events" ' +
+                'event_open_popup="true" '+
+                'date_start="start" '+
+                'quick_add="False" '+
+                'date_stop="stop" '+
+                'all_day="allday" '+
+                'mode="month" '+
+                'readonly_form_view_id="1">'+
+                    '<field name="name"/>'+
+            '</calendar>',
+            archs: archs,
+            viewOptions: {
+                initialDate: initialDate,
+            },
+        });
+
+        var $cell = calendar.$('.fc-day-grid .fc-row:eq(2) .fc-day:eq(2)');
+        for (var i = 0; i < 5; i++) {
+            testUtils.dom.triggerMouseEvent($cell, "mousedown");
+            testUtils.dom.triggerMouseEvent($cell, "mouseup");
+        }
+        def.resolve();
+        assert.equal(counter, 5, "there should had been 5 attemps to open a modal")
+        assert.containsOnce($('body'), '.modal', "there should be only one open modal");
+
+        calendar.destroy();
+    });
+
     QUnit.test('create event with timezone in week mode European locale', function (assert) {
         assert.expect(5);