New scheduling method is proposed in this paper, to consider the statistical distribution of machining time executed by human operators. The proposed scheduling method consists of two steps. In the first step, the sequences of jobs are determined for the individual machining tools based on dispatching rules. In the second step, the allocations of human operators to the individual machining tools are determined by considering the statistical deviations of the machining time. The scheduling system is also developed to carry out the proposed scheduling method by using machining time data base. The machining time data base generate the statistical deviations of the machining time obtained by the simulation of machining process.