Abstract: The Zakharov model is used to complete the full-scale simulation study of the generation of topside ionospheric turbulence. At the reflection point of O-mode waves, electromaganetic wave degenerates to two waves: plasma wave and ion acoustic wave. Then, the perturbation of electrons leads to the conversion from O-mode waves into Z-mode waves, and Z-mode waves could propagate into higher area. The result shows that in the millisecond magnitude scale, the Langmuir wave and ion acoustic wave are excited at the reflecton point of O-mode wave, and it leads to locally strong disturbance of electrons. The interaction between waves and particles makes O-mode wave convert into Z-mode wave and Z-mode wave propagates into higher area. In the topside of ionosphere, Z-mode wave excites the parametric decay instability and electrostatic field occurred. This study helps the understanding of the nonlinear interaction between HF wave and plasma in the ionosphere.