Objective To investigate the effectiveness and mechanism of recombinant human granulocyte-macrophage colony-stimulating factor (rhGMCSF) gel on wound debridement and healing of deep II thickness burn. Methods Between December 2008 and December 2010, 58 patients with deep II thickness burn, accorded with the inclusive criteria, were collected. There were 36 males and 22 females with an average age of 32.4 years (range, 12-67 years). The causes were hot liquid in 38 cases and fire in 20 cases. The time from injury to treatment was 1-3 days (mean, 2.1 days). In this randomized, double-blind, and self-control study, all patients were randomly divided into 2 groups, wounds were treated with rhGMCSF gel (test group) or gel matrix (control group). There was no significant difference in wound area between 2 groups (P gt; 0.05). The time of completed removal eschar and the percentage of removal-area of eschar were recorded at 2, 6, 10, 14, and 18 days during healing process. The time of wound healing was also recorded. Results Compared with control group, the necrotic tissues on the burn wound got soft in test group at 4 days after treatment. At 6 days, they loosened and eventually sloughed off. The wound bed presented in red and white, followed by rapidly growing granulation tissues. Except 18 days after treatment, there were significant differences in the percentage of removal-area of eschar between 2 groups (P lt; 0.05). The time of completed removal eschar in test group [(7.71 ± 2.76) days] was significantly shorter than that in control group [(14.71 ± 3.63) days] (t=13.726, P=0.000). The time of wound healing in test group was (18.41 ± 2.47) days, which was significantly shorter than that in control group [(23.58 ± 3.35) days] (t=15.763, P=0.000). Conclusion Compared with the gel matrix, the rhGMCSF gel may promote wound debridement and healing in deep II thickness burn.