The present invention provides a pet restraint system for a vehicle window that allows the pet access to outside air while being restrained from exiting the vehicle. The pet restraint system includes a plurality of spaced elongated transparent plastic strips removably secured to the vehicle window. Each of the elongated strips has a first end disposed to be received in the upper slot of a vehicle window frame, and a second end that carries a suction cup that adheres to the upper portion of a partially lowered vehicle window. The strips extend across the open area of the window frame and are spaced from each other at a distance that prevents the pet from exiting the vehicle.