Tape cassette (22) of the present disclosure configured to house roll body (RT) of a carrier tape includes housing (41) and shutter (42). Housing (41) includes housing space (41S) for housing roll body (RT) and front opening (41K) through which roll body (RT) is allowed to be taken in and out in a front part of housing (41). Shutter (42) can be displaced between a closing position at which movement of roll body (RT) to an outside of housing (41) through front opening (41K) is restricted by blocking at least a part of front opening (41K) and an open position at which the movement of roll body (RT) to the outside of housing (41) through front opening (41K) is allowed. Housing (41) is equipped on a component mounting device with front opening (41K) facing the component mounting device, and supplies roll body (RT) to the component mounting device with shutter (42) positioned at the open position.