The high-repetition rate optical pulses clock division is investigated based on the nonlinear dynamics of optically injected Fabry-Pérot semiconductor laser. A train of 6.32 GHz injected optical pulses divided into 3.16 GHz is obtained. Effects of the bias current of laser diode, the injected optical power, and injected optical spectrum etc. on the clock division, has been analyzed. The high-repetition rate optical pulses clock division is realized with the periodically oscillated nonlinear dynamics in optically injected F-P laser diode. The clock division will occur when the injected pulse spectral width is narrow, a certain longitudinal mode of the F-P laser diode is locked, and the conditions of low bias current and appropriate injected optical power are met. In addition, the effect of the laser bias currents, linewidth enhancement factor, and injected optical power on clock division is numerically investigated. Numerical simulations are consistent well with the experimental results.