An imaging device comprises a lens barrel having an optical system with an adjustable focal point, and has a first state can focus relative to an imaging face, and a second state can not focus relative to the imaging face, a changing unit for changing the lens barrel from the second state to the first state when the imaging unit is activated, a discriminating unit which discriminates whether the state of the barrel is the first state or the second state, and a control unit which, at a time of activating the imaging unit, changes the lens barrel to the first state by the changing unit if it is discriminated that the state of the barrel is the second state, and which maintains the first state if it is discriminated that the state of the barrel is the first state.