The generalized block-pulse operational matrices are derived as integral operators for operational calculus. In comparison with Walsh tables, the generalized operational matrices are nothing but the block-pulse tables. Further, it is pointed out that the conventional block-pulse operational matrix is a special case of the generalized operational matrices. Also, the generalized operational matrices are preferable to conventional block-pulse operational matrix when a given function is integrated repeatedly. Finally, the inverse Laplace transform of a rational transfer function via the generalized operational matrices is illustrated as an application of operational calculus.