The present disclosure provides a touch substrate, a touch display panel and a display device which belong to a field of touch display. The touch substrate includes a plurality of photo-sensing thin film transistor arranged on the substrate, the touch substrate further includes a piezoelectric sensing structure arranged above at least one of the photo-sensing thin film transistors, and a breakover current between a source and a drain of the photo-sensing thin film transistor corresponding to the piezoelectric sensing structure is changed, when the at least one piezoelectric sensing structure is pressed.