Four Ge2Sb2Te5 thin films were prepared by pulsed laser deposition (PLD) at 58, 100, 140, and 190 mJ/pulse laser energy, respectively. The influence of laser energy on the crystallization of Ge2Sb2Te5 was investigated. The result shows that laser energy has evident effect on the crystallization of Ge2Sb2Te5, including crystallization temperature, incubation time, Avrami coefficient, and grain size. The sample prepared at 140 mJ/pulse laser energy has the lowest crystallization temperature, the shortest incubation time, the largest Avrami coefficient, and the maximum mean grain size. The result of X-ray diffraction indicates that there are impurity-phase peaks in the pattern of the sample prepared at 190 mJ/pulse laser energy. A possible reason was given for these phenomenons.