The invention discloses a 
light sensing circuit and a driving method thereof, a display panel and a 
display device, belonging to the technical field of display. The 
light sensing circuit comprises that: the gate of a first 
transistor is electrically connected to a first control terminal, the first pole is electrically connected to a first 
voltage terminal, and the second pole is electrically connected to a first node; the gate of a second 
transistor is electrically connected to the first node, the first pole is electrically connected to a second 
voltage terminal, and the second pole is electrically connected to the first pole of a third 
transistor; the gate of the third transistor is electrically connected to a second control terminal, and the second pole is electrically connected to a data line; the gate of a fourth transistor is electrically connected to a third control terminal, the first pole is coupled to the first node, and the second pole is electrically connected to a third 
voltage terminal; the first transistor and the fourth transistor comprise active 
layers formed of 
metal oxide, and the fourth transistor is multiplexed into a 
light sensing element; and the second transistor and the third transistor comprise active 
layers formed of polysilicon. Compared with the prior art, the invention is advantageous to reduce the process steps and thin the display panel.