The invention discloses a linear type cutting seaming device, which comprises an upper jaw and a lower jaw capable of being closed or opened, wherein the far end of the lower jaw is provided with a nail cartridge; the lower jaw is in a U shape, and the lower jaw is internally provided with a percussion sheet and a push type cutter bar in a slidable manner. The linear type cutting seaming device also comprises a safety mechanism; the safety mechanism comprises a safety piece and an opening arranged on the percussion sheet and used for accommodating the safety piece. The safety piece can be driven to move along a direction perpendicular to the axis of the lower jaw by installing or removing the nail cartridge, and thus, the safety piece can be unclamped or clamped with the opening of the percussion sheet. The linear type cutting seaming device has the advantages of simple structure, convenient machining, safety and reliability, thereby having good popularization value.