diff --git a/change/react-native-windows-2020-05-21-22-04-55-PR-FixInstanceLoading.json b/change/react-native-windows-2020-05-21-22-04-55-PR-FixInstanceLoading.json
new file mode 100644
index 00000000000..3747500288b
--- /dev/null
+++ b/change/react-native-windows-2020-05-21-22-04-55-PR-FixInstanceLoading.json
@@ -0,0 +1,8 @@
+{
+  "type": "prerelease",
+  "comment": "Fix ReactInstance error state to avoid crashes",
+  "packageName": "react-native-windows",
+  "email": "vmorozov@microsoft.com",
+  "dependentChangeType": "patch",
+  "date": "2020-05-22T05:04:55.630Z"
+}
diff --git a/vnext/Microsoft.ReactNative/ReactHost/ReactInstanceWin.cpp b/vnext/Microsoft.ReactNative/ReactHost/ReactInstanceWin.cpp
index 151f0141364..4bd4ec76d51 100644
--- a/vnext/Microsoft.ReactNative/ReactHost/ReactInstanceWin.cpp
+++ b/vnext/Microsoft.ReactNative/ReactHost/ReactInstanceWin.cpp
@@ -407,7 +407,12 @@ void ReactInstanceWin::OnReactInstanceLoaded(const Mso::ErrorCode &errorCode) no
       if (auto strongThis = weakThis.GetStrongPtr()) {
         if (!strongThis->m_isLoaded) {
           strongThis->m_isLoaded = true;
-          strongThis->m_state = ReactInstanceState::Loaded;
+          if (!errorCode) {
+            strongThis->m_state = ReactInstanceState::Loaded;
+          } else {
+            strongThis->m_state = ReactInstanceState::HasError;
+          }
+
           if (auto onLoaded = strongThis->m_options.OnInstanceLoaded.Get()) {
             onLoaded->Invoke(*strongThis, errorCode);
           }
diff --git a/vnext/Microsoft.ReactNative/RedBox.cpp b/vnext/Microsoft.ReactNative/RedBox.cpp
index e7eb49bad95..74e6048b640 100644
--- a/vnext/Microsoft.ReactNative/RedBox.cpp
+++ b/vnext/Microsoft.ReactNative/RedBox.cpp
@@ -46,10 +46,12 @@ struct RedBox : public std::enable_shared_from_this<RedBox> {
   }
 
   void WindowSizeChanged(winrt::Windows::UI::Core::WindowSizeChangedEventArgs const &args) noexcept {
-    m_redboxContent.MaxHeight(args.Size().Height);
-    m_redboxContent.Height(args.Size().Height);
-    m_redboxContent.MaxWidth(args.Size().Width);
-    m_redboxContent.Width(args.Size().Width);
+    if (m_redboxContent) {
+      m_redboxContent.MaxHeight(args.Size().Height);
+      m_redboxContent.Height(args.Size().Height);
+      m_redboxContent.MaxWidth(args.Size().Width);
+      m_redboxContent.Width(args.Size().Width);
+    }
   }
 
   void ShowNewJSError() noexcept {
@@ -138,6 +140,7 @@ struct RedBox : public std::enable_shared_from_this<RedBox> {
     m_reloadButton.Click(m_tokenReload);
     xaml::Window::Current().SizeChanged(m_tokenSizeChanged);
     m_popup.Closed(m_tokenClosed);
+    m_redboxContent = nullptr;
     m_onClosedCallback(GetId());
   }