The explosion process of steam laser cleaning of printed circuit board (PCB) is simulated by using Ansys/Ls-Dyna finite element analysis software (FEA). Comparison with the theoretical adhere pressure of the particles and the propulsive pressure calculation are also carried out. The result shows that under the chosen conditions (energy density 1 J/cm2) the propulsive pressure on the particles which is in micron size or submicron size is larger than their adhere pressure but less than the destroy pressure of the PCB, so the micron or submicron particles are rencoved effectively without damaging the PCB. This proves that the steam laser cleaning can be uesed to clean PCB. From the simulation result, it is found that for laser cleaning of PCB, the laser pulse duration should be no more than 100 ns.