The invention relates to a cabin opening type ammunition mother bomb dissembling machine and method. The dissembling machine comprises a mother bomb lifting device and a mother bomb dissembling device; the mother bomb dissembling device comprise a dissembling table, a mother bomb loading manipulator arranged on the dissembling table, a positioning clamping mechanism for clamping a mother bomb, a rotating mechanism for driving the positioning clamping mechanism to rotate, a bottom-bolt dissembling device body for dissembling mother bomb bottom bolts, a fixed-length pushing-out device body for pushing out fillers in the mother bomb, a fixing rib and key dissembling manipulator, a sub bomb dissembling manipulator and a mechanical arm for driving one of the fixing rib and key dissembling manipulator and the sub bomb dissembling manipulator to conduct actions, wherein the fixing rib and key dissembling manipulator and the sub bomb dissembling manipulator are arranged above the positioning clamping mechanism. According to the cabin opening type ammunition mother bomb dissembling machine and method, the structure is simple, operating is easy, convenient, safe and reliable, the automation degree is high, and automatic and efficient dissembling of the various cabin opening type ammunition mother bombs can be achieved; and the bottom bolts are dissembled firstly, then the fillers are pushed out, and dissembling of components, such as bomb shells, the bottom bolts and the fillers, of the cabin opening type ammunition mother bombs is achieved.