A hybrid task scheduling method is presented, in which strict periodicity criteria is adopted to certain important or easy-to-schedule tasks, while the rest is scheduled based on the jitter minimization criteria to mitigate the variance of intervals between any two adjacent jobs of a given task. To develop this method, a measure for strict periodicity schedulability, and a feasible slot selection scheme for variable-length jobs are proposed. The min-plus algebra is used for making multiplication of weighted transferring matrix, thus to implement slot allocation with minimum jitter of current task. Case study shows that: Compared with the control groups only based on minimum jitter scheduling, our hybrid method can gain increased proportion of strictly periodic tasks and the scheduling scheme obtained has smaller jitter rate in the worst case.