Gravitational formulae of two remnant spherical shells are given in this paper and are used in stone slab correction and topographic correction for gravity survey. The results of the correction have been compared with the corresponding values calculated by finite and infinite plane formulae commonly used in the past, which shows that, in using the plane formula to conduct correction, the error resulting from the imperfection of the model can not be neglected in many cases.The variability in sign of the topographic correction values is also dealt with in this paper with the aid of the remnant spherical shell model.In view of the wide utilization of the microcomputer, the author suggests that the remnant spherical model should be used in stone slab correction and topographic correction.