A tandem color image forming apparatus includes a plurality of
photosensitive bodies driven by one driving source and having a shaft
gear, and power transmission members engaged with the shaft gears of the
plurality of the photosensitive bodies to transmit a driving force
generated from the driving source to each of the plurality of the
photosensitive bodies. At least one color registration compensation unit
is disposed between the power transmission members. The color image
forming apparatus employs the color registration compensation unit so
that each photosensitive body can be synchronized and registration errors
can be minimized.