According to an embodiment of the present invention, a sheet detection apparatus that detects a sheet includes an actuator unit that is rotatable around a rotational axis so as to adopt any of a protruding position in which the actuator unit protrudes into a detection area for detecting the sheet and a retracted position in which the actuator unit is retracted from the detection area, and an operation unit that is capable of switching between a retracted state in which the actuator unit is set to the retracted position and a protruding state in which the actuator unit is set to the protruding position. An image forming apparatus according to an embodiment of the present invention includes the sheet detection apparatus, and the sheet detection apparatus is provided in a main body of the image forming apparatus.