diff --git a/plugins/tasks/tasks-core/src/com/intellij/tasks/redmine/RedmineRepository.java b/plugins/tasks/tasks-core/src/com/intellij/tasks/redmine/RedmineRepository.java
index 2c1fca1df9db..be9bb2cb8da2 100644
--- a/plugins/tasks/tasks-core/src/com/intellij/tasks/redmine/RedmineRepository.java
+++ b/plugins/tasks/tasks-core/src/com/intellij/tasks/redmine/RedmineRepository.java
@@ -44,24 +44,26 @@ public class RedmineRepository extends NewBaseRepositoryImpl {
   private static final Pattern ID_PATTERN = Pattern.compile("\\d+");
   private static final Logger LOG = Logger.getInstance(RedmineRepository.class);
   
-  public static final RedmineProject UNSPECIFIED_PROJECT = new RedmineProject() {
-    @NotNull
-    @Override
-    public String getName() {
-      return "-- from all projects --";
-    }
+  public static final RedmineProject UNSPECIFIED_PROJECT = createUnspecifiedProject();
 
-    @Nullable
-    @Override
-    public String getIdentifier() {
-      return getName();
-    }
+  @NotNull
+  private static RedmineProject createUnspecifiedProject() {
+    final RedmineProject unspecified = new RedmineProject() {
+      @NotNull
+      @Override
+      public String getName() {
+        return "-- from all projects --";
+      }
 
-    @Override
-    public int getId() {
-      return -1;
-    }
-  };
+      @Nullable
+      @Override
+      public String getIdentifier() {
+        return getName();
+      }
+    };
+    unspecified.setId(-1);
+    return unspecified;
+  }
 
   private String myAPIKey = "";
   private RedmineProject myCurrentProject;
diff --git a/plugins/tasks/tasks-tests/test/com/intellij/tasks/integration/RedmineIntegrationTest.java b/plugins/tasks/tasks-tests/test/com/intellij/tasks/integration/RedmineIntegrationTest.java
index 86e7cc9a2c45..ffc4fea464b6 100644
--- a/plugins/tasks/tasks-tests/test/com/intellij/tasks/integration/RedmineIntegrationTest.java
+++ b/plugins/tasks/tasks-tests/test/com/intellij/tasks/integration/RedmineIntegrationTest.java
@@ -1,5 +1,6 @@
 package com.intellij.tasks.integration;
 
+import com.intellij.configurationStore.XmlSerializer;
 import com.intellij.tasks.Task;
 import com.intellij.tasks.TaskBundle;
 import com.intellij.tasks.TaskManagerTestCase;
@@ -9,6 +10,8 @@ import com.intellij.tasks.redmine.RedmineRepository;
 import com.intellij.tasks.redmine.RedmineRepositoryType;
 import com.intellij.tasks.redmine.model.RedmineProject;
 import com.intellij.util.containers.ContainerUtil;
+import one.util.streamex.StreamEx;
+import org.jdom.Element;
 
 import java.util.List;
 
@@ -133,6 +136,18 @@ public class RedmineIntegrationTest extends TaskManagerTestCase {
     }
   }
 
+  // IDEA-200933
+  public void testUnspecifiedProjectIdSerialized() {
+    myRepository.setCurrentProject(RedmineRepository.UNSPECIFIED_PROJECT);
+    final List<Element> options = XmlSerializer.serialize(myRepository).getChildren("option");
+    final String serializedId = StreamEx.of(options)
+      .findFirst(elem -> "currentProject".equals(elem.getAttributeValue("name")))
+      .map(elem -> elem.getChild("RedmineProject"))
+      .map(elem -> elem.getAttributeValue("id"))
+      .orElse(null);
+    assertEquals("-1", serializedId);
+  }
+
   @Override
   public void setUp() throws Exception {
     super.setUp();