diff --git a/libs/pyTermTk/TermTk/TTkUiTools/properties/tree.py b/libs/pyTermTk/TermTk/TTkUiTools/properties/tree.py
index 6df9ea89..e4ed8bbd 100644
--- a/libs/pyTermTk/TermTk/TTkUiTools/properties/tree.py
+++ b/libs/pyTermTk/TermTk/TTkUiTools/properties/tree.py
@@ -41,5 +41,7 @@ TTkTreeProperties = {
         'itemExpanded(TTkTreeWidgetItem)'          : {'name' : 'itemExpanded'      ,  'type': TTkTreeWidgetItem},
         'itemCollapsed(TTkTreeWidgetItem)'         : {'name' : 'itemCollapsed'     ,  'type': TTkTreeWidgetItem},
     },'slots' : {
+        'expandAll()'   : {'name': 'expandAll',   'type':None},
+        'collapseAll()' : {'name': 'collapseAll', 'type':None},
     }
 }
diff --git a/libs/pyTermTk/TermTk/TTkWidgets/TTkModelView/tree.py b/libs/pyTermTk/TermTk/TTkWidgets/TTkModelView/tree.py
index d12342f6..02682e6b 100644
--- a/libs/pyTermTk/TermTk/TTkWidgets/TTkModelView/tree.py
+++ b/libs/pyTermTk/TermTk/TTkWidgets/TTkModelView/tree.py
@@ -42,6 +42,7 @@ class TTkTree(TTkAbstractScrollArea):
             'setColumnWidth', 'resizeColumnToContents',
             'sortColumn', 'sortItems',
             'dragDropMode', 'setDragDropMode',
+            'expandAll', 'collapseAll',
             # 'appendItem', 'setAlignment', 'setColumnColors', 'setColumnSize', 'setHeader',
             'addTopLevelItem', 'addTopLevelItems', 'takeTopLevelItem', 'topLevelItem', 'indexOfTopLevelItem', 'selectedItems', 'clear'])
         )
diff --git a/libs/pyTermTk/TermTk/TTkWidgets/TTkModelView/treewidget.py b/libs/pyTermTk/TermTk/TTkWidgets/TTkModelView/treewidget.py
index edc4ff37..1ae58471 100644
--- a/libs/pyTermTk/TermTk/TTkWidgets/TTkModelView/treewidget.py
+++ b/libs/pyTermTk/TermTk/TTkWidgets/TTkModelView/treewidget.py
@@ -337,6 +337,26 @@ class TTkTreeWidget(TTkAbstractScrollView):
         contentSize = max(row.data[column].termWidth() for row in self._cache)
         self.setColumnWidth(column, contentSize)
 
+    @pyTTkSlot()
+    def expandAll(self) -> None:
+        '''expandAll'''
+        if not self._rootItem:
+            return
+        self._rootItem.dataChanged.disconnect(self._refreshCache)
+        self._rootItem.expandAll()
+        self._rootItem.dataChanged.connect(self._refreshCache)
+        self._refreshCache()
+
+    @pyTTkSlot()
+    def collapseAll(self) -> None:
+        '''collapseAll'''
+        if not self._rootItem:
+            return
+        self._rootItem.dataChanged.disconnect(self._refreshCache)
+        self._rootItem.collapseAll()
+        self._rootItem.dataChanged.connect(self._refreshCache)
+        self._refreshCache()
+
     def mouseDoubleClickEvent(self, evt:TTkMouseEvent) -> bool:
         x,y = evt.x, evt.y
         ox, oy = self.getViewOffsets()
diff --git a/libs/pyTermTk/TermTk/TTkWidgets/TTkModelView/treewidgetitem.py b/libs/pyTermTk/TermTk/TTkWidgets/TTkModelView/treewidgetitem.py
index 2cdabece..e0c4ab57 100644
--- a/libs/pyTermTk/TermTk/TTkWidgets/TTkModelView/treewidgetitem.py
+++ b/libs/pyTermTk/TermTk/TTkWidgets/TTkModelView/treewidgetitem.py
@@ -305,6 +305,16 @@ class TTkTreeWidgetItem(TTkAbstractItemModel):
             return None
         return self._widgets[col]
 
+    def expandAll(self) -> None:
+        for child in self._children:
+            child.setExpanded(True)
+            child.expandAll()
+
+    def collapseAll(self) -> None:
+        for child in self._children:
+            child.setExpanded(False)
+            child.collapseAll()
+
     def sortData(self, col):
         return self.data(col)