diff --git a/lib/xcodeproj/project/object/helpers/groupable_helper.rb b/lib/xcodeproj/project/object/helpers/groupable_helper.rb
index 1ae19fb43..73637fcf4 100644
--- a/lib/xcodeproj/project/object/helpers/groupable_helper.rb
+++ b/lib/xcodeproj/project/object/helpers/groupable_helper.rb
@@ -153,7 +153,7 @@ def source_tree_real_path(object)
                 real_path(object_parent)
               end
             when 'SOURCE_ROOT'
-              object.project.project_dir
+              object.project.project_dir + object.project.root_object.project_dir_path
             when '<absolute>'
               nil
             else
diff --git a/spec/project/object/helpers/groupable_helper_spec.rb b/spec/project/object/helpers/groupable_helper_spec.rb
index 9e2b9c707..ebbf89818 100644
--- a/spec/project/object/helpers/groupable_helper_spec.rb
+++ b/spec/project/object/helpers/groupable_helper_spec.rb
@@ -183,13 +183,20 @@ module ProjectSpecs
         @helper.source_tree_real_path(@group).should == Pathname.new('/project_dir')
       end
 
-      it 'check project_dir_path adjustment' do
+      it 'check project_dir_path adjustment relative to main group' do
         @group.source_tree = '<group>'
         @project.root_object.stubs(:project_dir_path).returns('../')
         @helper.source_tree_real_path(@group).to_s.should.not.include Pathname.new('/project_dir').to_s
         Pathname.new('/project_dir').to_s.should.include @helper.source_tree_real_path(@group).to_s
       end
 
+      it 'check project_dir_path adjustment relative to project root' do
+        @group.source_tree = 'SOURCE_ROOT'
+        @project.root_object.stubs(:project_dir_path).returns('../')
+        @helper.source_tree_real_path(@group).to_s.should.not.include Pathname.new('/project_dir').to_s
+        Pathname.new('/project_dir').to_s.should.include @helper.source_tree_real_path(@group).to_s
+      end
+
       it 'returns the source tree of a path relative to a group' do
         @group.source_tree = '<absolute>'
         @group.path = '/parent_group_path'