To provide a photoelectric conversion apparatus from which a sufficient photoelectric conversion amount can be obtained, resulting in that an optimum sensitivity corresponding to a read speed of an original and an emission luminous quantity to the original can be obtained and to provide an image reading apparatus provided with the photoelectric conversion apparatus and a photoelectric conversion method.

The photoelectric conversion apparatus charges up electric charges to an auxiliary capacitor 17 connected to a drain D of a TFT 7 including a photoelectric conversion element by a prescribed amount, brings the TFT 7 to a nonconductive state, emits light to the TFT 7 for a prescribed time after the electric charges by the prescribed amount applied to the auxiliary capacitor 17 is finished, and thereafter senses a photoelectric conversion amount of a sensor substrate 20 including the TFT 7 on the basis of the electric charges charged onto the auxiliary capacitor 17, and the photoelectric conversion apparatus includes a drive IC 19 for applying a gate voltage to a gate G of the TFT 7 when the TFT 7 is brought into the nonconductive state and the light is emitted to the TFT 7 for the prescribed time, and a control/communication board 24 for applying variable control to the gate voltage applied by the drive IC 19.