This paper describes fracture mechanics simulation with a partitioned iterative coupling method. Here an analysis object, i.e. a cracked structure, is decomposed into two domains, i.e. the one with a crack and the other without crack, both of which are analyzed separately. The size of the cracked domain is smaller, whereas the other domain is much larger. Fracture mechanics analysis is performed only in the small domain. To satisfy both geometric compatibility and force equilibrium on the boundary of the two domains, the two domains are analyzed repeatedly till getting convergence using some iterative solution technique. A benchmark analysis was performed to validate the method and to evaluate computational performance. The computed stress intensity factors were as accurate as those obtained using a conventional FEM and theoretical solution, while computational performance was comparable.