Objective: To observe the changes of miRNA-199a-5p expression in human skin fibroblasts with thermal injury and its effects on the proliferation, migration and invasion of skin fibroblasts. Methods: Cell models of thermal injury were established using human skin fibroblast cell line by bathing in water at 52℃ for 30 s and 60 s, respectively, and the thermal injury of cells was observed and compared. The proliferation rate of cells 24 h and 48 h after thermal injury was detected by MTT assay. The changes of miRNA-199a-5p expression in the cells 24 and 48 h after thermal injury were determined through QRT-PCR. Cell migration and invasion were detected using wound-healing assay and Transwell assay. The expression of miRNA-199a-5p in thermally injured cells was increased using mimics, and the proliferation and invasion of thermally injured cells were detected. Results: Bathing in water at 52℃ for 30 s could successfully establish a thermal injury model in human skin fibroblasts. After thermal injury, miRNA-199a-5p expression was down-regulated (24h，2.67±0.35%，P＜0.001；48h，18.42±0.44%，P＜0.001), cell proliferation was significantly inhibited（24h，17.10±3.21%，P＜0.002；48h，25.93.10±1.74%，P＜0.001）, cell migration decreased significantly（35.35±7.07%，P＜0.001）, and cell invasion was also significantly inhibited（57.14±9.52%，P＜0.007）. After enhancing miRNA-199a-5p expression in the thermally injured cells using mimics, the proliferation of the cells increased significantly（136.55±6.14%,P＜0.003）, and the invasion ability of the cells was enhanced（136.55±6.14%,P＜0.003）.Conclusions: The expression level of miRNA-199a-5p in human skin fibroblasts with thermal injury is positively correlated with cell proliferation, migration and invasion. Increasing the expression level of miRNA-199a-5p in thermally injured cells can help it rapid return.