In order to explore a new mulch-free maize planting mode and the best seedling age for maize transplantation in Shanxi early mature area, a field experiment was carried out using completely randomized block design. Taking mulch-based direct sowing as the control group, effects of transplantation in different stage on maize growing process, plant height, three-ear leaf area in mature period, and yield and composition factors of maize. Results indicate that growing process of maize seedlings transplanted in every stage is slightly slower than the control group. Transplantation has effect of reducing plant height and three-ear leaf area in mature period. There was no significant difference between the yield of maize transplanted on May 1st and the control group, and the yield declined only by 7% compared with mulch-based direct sowing (CK). Damages to maize seedlings by the local late frost must be noticed when maize is planted by the method of mulch-free transplantation in early mature area. Transplanting the seedlings earlier after the late frost is deemed as an appropriate period in this area.