An interchangeable lens camera includes a camera body and a lens unit. The camera body includes: a body-side mount section; a mounting determination section; a body-side communication section; and a body control section. The lens unit includes a lens-side mount section and a lens-side communication section. A specific body-side signal terminal among plural body-side signal terminals of the camera body is connected to a power supply through a pull-up resistor, and a specific lens-side signal terminal, which is capable of coming into contact with the specific body-side signal terminal, among plural lens-side signal terminals of the lens unit is grounded through a pull-down resistor. The mounting determination section determines that the lens unit is mounted on the body-side mount section when resistance values of both the specific body-side signal terminal at time of non-communication and a body-side detection terminal of the camera body are at low levels.