McKeague offered a new method for verification of off-line signature based on Bayesian Model and Markov ChainMonte Carlo (MCMC), in which smoothness of the signature curve seems a necessity (it should have no singular point), but when a signature is piecewise smooth, can we use this method for verification of this signature? If yes, how can we use that? And is this method appropriate for piecewise-smooth signatures too? In the current article, we give an idea for verification of a piecewise smooth signature based on McKeague’s method. We suggest to separate the smooth segments from singular points and then each segment is verified by McKeague’s method independently. Finally, according to the result from smooth segments, we determine the correctness of this signature. Then we will check the validity of this idea with computing errors via simulation.