Abstract: Jaw crushing and cone crushing of slurry balanced shield machines are different in terms of strata suitability and tunnel size. If only one crushing mode is used in one more complicated tunnel engineering, the construction efficiency of shield machines will be lower. In order to solve this problem, the crushing mechanisms of shield machines were investigated, and then slurry balanced shield machines were transformed by adopting the compound crushing mode. The transformation was carried out in four steps, i.e., sealing of slurry cabin, design and installation of cone crushing tendon, design and installation of grid baffle, and transformation of supporting nozzle of cone crushing system. The transformed slurry shield machine is equipped with two crushing modes, so its adaptability to various strata is improved and its tunneling efficiency in complex strata is increased by 20%.