We investigated motion integration properties of the perception of motion aftereffect caused by wide-field transparent visual flow. Adapting stimulus composed of random dot patterns was presented to human observers to examine both direction and duration of motion aftereffect(MAE). For unidirectional motion, perceived duration of MAE depended on the speed of adapting stimulus. Transparent visual stimulus in the multiple directions induced motion aftereffect with unidirectional percept. Perceived direction depended on the speed of coherent motion in the transparent visual flow. Direction of motion aftereffect suggested linear integration mechanism of transparent flows by weighted summation of each coherent motion in the visual stimulus.