Abstract: Solving dynamics equations of plasma in fusion-fission hybrid reactor core is performed by using Runge-kutta method.Taking different step-length at different time segment is used through computation which can ensure the solution accuracy and save CPU time. There obtained solution curves fully display burning process of plasma in reactor core. In addition, value feedack control method applies to optimization and control of solution curves.

Key words: dynamics equations of plasma, fusion-fission hybrid reactor, value feedback control