A lever type connector is provided with a lever assisting in fitting or detaching first and second connector housings thereof. A lever is fitted to the first connector housing. A plurality of projecting parts is provided in a circumference of the lever. A plurality of receiving parts is provided in the first connector housing to slidably engage with the projecting part. Engagement between the projecting and receiving parts prevents the lever from deformation and warpage in a rotating operation of the lever for the connecting operation. The projecting parts and the receiving parts are configured so that the projecting parts and the receiving parts are engaged only when the lever is positioned so that the fitting force is large in the rotating operation, and the projecting parts and the receiving parts are not engaged when the lever is positioned in another state in which the fitting force is small.