diff --git a/fpdfsdk/fpdf_formfill_embeddertest.cpp b/fpdfsdk/fpdf_formfill_embeddertest.cpp
index 56917e2..12c303b 100644
--- a/fpdfsdk/fpdf_formfill_embeddertest.cpp
+++ b/fpdfsdk/fpdf_formfill_embeddertest.cpp
@@ -2309,6 +2309,81 @@
   CheckSelection(L"ABCDEHello");
 }
 
+TEST_F(FPDFFormFillComboBoxFormEmbedderTest,
+       CheckIfEnterAndSpaceKeyAreHandled) {
+  // Non-editable field is set to 'Banana' (index 1) upon opening.
+  ClickOnFormFieldAtPoint(NonEditableFormBegin());
+  CheckIsIndexSelected(0, false);
+  CheckIsIndexSelected(1, true);
+
+  // Verify that the Enter key is handled.
+  EXPECT_TRUE(FORM_OnChar(form_handle(), page(), FWL_VKEY_Return, 0));
+
+  // Change the selection in the combo-box using the arrow down key.
+  EXPECT_TRUE(FORM_OnKeyDown(form_handle(), page(), FWL_VKEY_Down, 0));
+  CheckIsIndexSelected(1, false);
+  CheckIsIndexSelected(2, true);
+
+  // Tab to the next control.
+  EXPECT_TRUE(FORM_OnChar(form_handle(), page(), FWL_VKEY_Tab, 0));
+
+  // Shift-tab to the previous control.
+  EXPECT_TRUE(
+      FORM_OnChar(form_handle(), page(), FWL_VKEY_Tab, FWL_EVENTFLAG_ShiftKey));
+
+  // Verify that the selection is unchanged.
+  CheckIsIndexSelected(2, true);
+
+  // Verify that the Space key is handled.
+  EXPECT_TRUE(FORM_OnChar(form_handle(), page(), FWL_VKEY_Space, 0));
+
+  // Change the selection in the combo-box using the arrow down key.
+  EXPECT_TRUE(FORM_OnKeyDown(form_handle(), page(), FWL_VKEY_Down, 0));
+  CheckIsIndexSelected(3, true);
+
+  // Tab to the next control.
+  EXPECT_TRUE(FORM_OnChar(form_handle(), page(), FWL_VKEY_Tab, 0));
+
+  // Shift-tab to the previous control.
+  EXPECT_TRUE(
+      FORM_OnChar(form_handle(), page(), FWL_VKEY_Tab, FWL_EVENTFLAG_ShiftKey));
+
+  // Verify that the selection is unchanged.
+  CheckIsIndexSelected(3, true);
+}
+
+TEST_F(FPDFFormFillComboBoxFormEmbedderTest,
+       CheckIfEnterAndSpaceKeyAreHandledOnEditableFormField) {
+  // Non-editable field is set to 'Banana' (index 1) upon opening.
+  ClickOnFormFieldAtPoint(EditableFormBegin());
+  CheckIsIndexSelected(0, false);
+  CheckIsIndexSelected(1, false);
+
+  // Verify that the Enter key is handled.
+  EXPECT_TRUE(FORM_OnChar(form_handle(), page(), FWL_VKEY_Return, 0));
+
+  // Change the selection in the combo-box using the arrow down key.
+  EXPECT_TRUE(FORM_OnKeyDown(form_handle(), page(), FWL_VKEY_Down, 0));
+  CheckIsIndexSelected(0, true);
+  CheckIsIndexSelected(1, false);
+
+  // Tab to the next control.
+  EXPECT_TRUE(FORM_OnChar(form_handle(), page(), FWL_VKEY_Tab, 0));
+
+  // Shift-tab to the previous control.
+  EXPECT_TRUE(
+      FORM_OnChar(form_handle(), page(), FWL_VKEY_Tab, FWL_EVENTFLAG_ShiftKey));
+
+  // Verify that the selection is unchanged.
+  CheckIsIndexSelected(0, true);
+
+  // Verify that the Space key is handled.
+  EXPECT_TRUE(FORM_OnChar(form_handle(), page(), FWL_VKEY_Space, 0));
+
+  CheckFocusedFieldText(L" ");
+  CheckIsIndexSelected(0, false);
+}
+
 TEST_F(FPDFFormFillTextFormEmbedderTest,
        InsertTextInEmptyCharLimitTextFieldOverflow) {
   // Click on the textfield.
diff --git a/fpdfsdk/pwl/cpwl_combo_box.cpp b/fpdfsdk/pwl/cpwl_combo_box.cpp
index a821d0c..d23a905 100644
--- a/fpdfsdk/pwl/cpwl_combo_box.cpp
+++ b/fpdfsdk/pwl/cpwl_combo_box.cpp
@@ -533,6 +533,28 @@
   if (!m_pEdit)
     return false;
 
+  // In a combo box if the ENTER/SPACE key is pressed, show the combo box
+  // options.
+  switch (nChar) {
+    case FWL_VKEY_Return:
+      SetPopup(!IsPopup());
+      SetSelectText();
+      return true;
+    case FWL_VKEY_Space:
+      // Show the combo box options with space only if the combo box is not
+      // editable
+      if (!HasFlag(PCBS_ALLOWCUSTOMTEXT)) {
+        if (!IsPopup()) {
+          SetPopup(/*bPopUp=*/true);
+          SetSelectText();
+        }
+        return true;
+      }
+      break;
+    default:
+      break;
+  }
+
   m_nSelectItem = -1;
   if (HasFlag(PCBS_ALLOWCUSTOMTEXT))
     return m_pEdit->OnChar(nChar, nFlag);
diff --git a/testing/resources/pixel/combobox_form.evt b/testing/resources/pixel/combobox_form.evt
new file mode 100644
index 0000000..8211937
--- /dev/null
+++ b/testing/resources/pixel/combobox_form.evt
@@ -0,0 +1,10 @@
+# Check the combobox control
+mousemove,102,410
+mousedown,left,102,410
+mouseup,left,102,410
+
+# Press Enter to open the pop-up menu
+charcode,13
+
+# Press Space to make sure that the pop-up is not dismissed
+charcode,32
\ No newline at end of file
diff --git a/testing/resources/pixel/combobox_form.in b/testing/resources/pixel/combobox_form.in
new file mode 100644
index 0000000..56adea4
--- /dev/null
+++ b/testing/resources/pixel/combobox_form.in
@@ -0,0 +1,35 @@
+{{header}}
+{{object 1 0}} <<
+  /Type /Catalog
+  /Pages 2 0 R
+  /AcroForm <<
+    /Fields [4 0 R]
+  >>
+>>
+endobj
+{{object 2 0}} <<
+  /Type /Pages
+  /Count 1
+  /Kids [3 0 R]
+>>
+endobj
+{{object 3 0}} <<
+  /Type /Page
+  /Parent 2 0 R
+  /Annots [4 0 R]
+>>
+endobj
+{{object 4 0}} <<
+  /Type /Annot
+  /Subtype /Widget
+  /FT /Ch
+  /Ff 131072
+  /T (Combo)
+  /Rect [100 400 200 430]
+  /Opt [() () ()]
+>>
+endobj
+{{xref}}
+{{trailer}}
+{{startxref}}
+%%EOF
diff --git a/testing/resources/pixel/combobox_form_expected.pdf.0.png b/testing/resources/pixel/combobox_form_expected.pdf.0.png
new file mode 100644
index 0000000..7ecd75d
--- /dev/null
+++ b/testing/resources/pixel/combobox_form_expected.pdf.0.png
Binary files differ