Abstract: In order to solve the problem of distribution cam mechanism vibration, crash and noise in operation, a dynamical optimization model regarding distribution cam mechanism in internal combustion engine was developed. Based on ant colony algorithms and MATLAB, optimization programs concerning the model were developed and simulation was conducted. Compared with original design, the simulation results show that plentiful coefficient increased by 1.24%, dynamical maximum positive acceleration lowers by 0.87% in ascending and increases by 5.23% in descending. The maximum negative acceleration decreases by 5.93%. All these make system dynamical velocity and dynamical acceleration stable and reduce shock vibration effectively, the optimization effect is better than genetic algorithms do.