Abstract: An automatic solar-powered car ventilator to be installed between the upper horizontal bar of the window sash and the upper horizontal edge of a movable window glass in a window in a car door having a main body and two auxiliary bodies extending from both sides of the main body to be cut to suit the width of the movable window glass. A ventilating means including a fan, a motor to drive the fan to suck in the open air and exhaust out the air in the car. A base to mount the fan and the motor and a housing to shield the fan, the motor and the base. A solar-energy board being combined with the main body or the ventilating means by means of two clamps on the board movably catching hold of either two holders on the main body or on the ventilating means to generate electricity to power the motor by absorbing the sunlight.