A solid-state image pick-up apparatus of an example includes a photoelectric conversion portion, a transfer transistor configured to transfer a charge in the photoelectric conversion portion, and a signal output circuit configured to supply selectively a first voltage to turn on the transfer transistor and a second voltage to turn off the transfer transistor to the transfer transistor. The signal output circuit is configured to supply the second voltage having a voltage value selected from two or more different voltage values based on an output signal from a pixel.