In this paper, the cracking behavior of concrete tunnel lining is simulated by a finite element code with smeared crack model. Based on the experimental observation, numerical simulations are carried out in the following aspects: 1) initial imperfection; 2) concrete tensile strength; 3) fracture energy; 4) load direction; 5) size effect on structural strength and 6) soil mass constrain. The analyses on the items of 1) through 3) treat the basic factors affecting the cracking behavior of tunnel lining. And studies of 4) through 6) can provide a better understanding of tunnel lining response under complicated conditions.