To explore more simple and efficient ion extraction methods used in atomic vapor laser isotope separation (AVLIS),two-dimensional(2D) PIC-MCC simulation code is used to simulate and compare several methods: parallel electrode method,Π type electrode method,improved M type electrode method,and radio frequency (RF) reso nance method.The simulations show that,the RF resonance method without magnetic field is the best among others,then the improved M type electrode method.The res ult of simulation of Π type electrode method is quite different from that calcu lated by 2D electron equilibrium model.The RF resonance method with or without m agnetic field has guite different results.Strong resonance occurs in the simulation without magnetic field,whereas no significant resonance occurs under weak magnetic field.And that is quite different from the strong resonance phenomena occurving in the 1D PIC simulation with weak magnetic field.As for practical applications,the RF resonance method without magnetic field has pros and cons, compare d with the M type electrode method.