A color wheel with dovetailed balancing groove, includes a motor, a metal ring and a set of color filter set. At a rotatable portion of the color wheel, such as the peripheral portion between the metal ring and the housing of the motor, or on the peripheral surface of the metal ring, a balancing groove with narrow opening and wider inside is formed thereon. Using the feature of a narrow opening and wider inside, glue is added into the opening and dries to become solid balancing material. The color wheel is less prone to deviate from the metal ring, even though a relative larger centrifugal force is induced and acted thereon while the color is running at higher speed and higher temperature.