diff --git a/python/plugins/processing/gui/FixedTableDialog.py b/python/plugins/processing/gui/FixedTableDialog.py
index 5d481f24f48..1b1f9e3efe5 100644
--- a/python/plugins/processing/gui/FixedTableDialog.py
+++ b/python/plugins/processing/gui/FixedTableDialog.py
@@ -81,7 +81,7 @@ class FixedTableDialog(BASE, WIDGET):
         # Populate table
         for i in range(rows):
             for j in range(cols):
-                item = QStandardItem(table[i][j])
+                item = QStandardItem(str(table[i][j]))
                 model.setItem(i, j, item)
         self.tblView.setModel(model)
 
diff --git a/python/plugins/processing/gui/FixedTablePanel.py b/python/plugins/processing/gui/FixedTablePanel.py
index b5597da2725..52a8225512f 100644
--- a/python/plugins/processing/gui/FixedTablePanel.py
+++ b/python/plugins/processing/gui/FixedTablePanel.py
@@ -56,11 +56,16 @@ class FixedTablePanel(BASE, WIDGET):
 
         self.btnSelect.clicked.connect(self.showFixedTableDialog)
 
+    def updateSummaryText(self):
+        self.leText.setText(self.tr('Fixed table {0}x{1}').format(
+            len(self.table), len(self.param.headers())))
+
+    def setValue(self, value):
+        self.table = value
+        self.updateSummaryText()
+
     def showFixedTableDialog(self):
         dlg = FixedTableDialog(self.param, self.table)
         dlg.exec_()
         if dlg.rettable is not None:
-            self.table = dlg.rettable
-
-        self.leText.setText(self.tr('Fixed table {0}x{1}').format(
-            len(self.table), len(self.param.headers())))
+            self.setValue(dlg.rettable)
diff --git a/python/plugins/processing/gui/wrappers.py b/python/plugins/processing/gui/wrappers.py
index 0e3193bc267..6b66e823d10 100755
--- a/python/plugins/processing/gui/wrappers.py
+++ b/python/plugins/processing/gui/wrappers.py
@@ -559,7 +559,7 @@ class FixedTableWidgetWrapper(WidgetWrapper):
         return FixedTablePanel(self.param)
 
     def setValue(self, value):
-        pass
+        self.widget.setValue(value)
 
     def value(self):
         if self.dialogType == DIALOG_MODELER:
diff --git a/python/plugins/processing/tests/GuiTest.py b/python/plugins/processing/tests/GuiTest.py
index 61de8d33096..e6231636d8e 100644
--- a/python/plugins/processing/tests/GuiTest.py
+++ b/python/plugins/processing/tests/GuiTest.py
@@ -28,6 +28,7 @@ __revision__ = '$Format:%H$'
 from qgis.testing import start_app, unittest
 from qgis.core import (QgsApplication,
                        QgsCoordinateReferenceSystem,
+                       QgsProcessingParameterMatrix,
                        QgsVectorLayer)
 from qgis.analysis import QgsNativeAlgorithms
 
@@ -158,6 +159,25 @@ class WrappersTest(unittest.TestCase):
 
         widget.deleteLater()
 
+    def testMatrix(self):
+        self.checkConstructWrapper(QgsProcessingParameterMatrix('test'), FixedTableWidgetWrapper)
+
+        alg = QgsApplication.processingRegistry().algorithmById('native:centroids')
+        dlg = AlgorithmDialog(alg)
+        param = QgsProcessingParameterMatrix('test', 'test', 2, True, ['x', 'y'], [['a', 'b'], ['c', 'd']])
+        wrapper = FixedTableWidgetWrapper(param, dlg)
+        widget = wrapper.createWidget()
+
+        # check that default value is initially set
+        self.assertEqual(wrapper.value(), [['a', 'b'], ['c', 'd']])
+
+        # test widget
+        widget.show()
+        wrapper.setValue([[1, 2], [3, 4]])
+        self.assertEqual(wrapper.value(), [[1, 2], [3, 4]])
+
+        widget.deleteLater()
+
     def testNumber(self):
         self.checkConstructWrapper(QgsProcessingParameterNumber('test'), NumberWidgetWrapper)