The present study evaluated the effect of non-thermal plasma on skin wound healing in BalB/c mice.Two 6-mm wounds along the both sides of the spine were created on the back of each mouse (n=80) by using a punch biopsy.The mice were assigned randomly into two groups,with 40animals in each group:a non-thermal plasma group in which the mice were treated with the non-thermal plasma; a control group in which the mice were left to heal naturally.Wound healing was evaluated on postoperative days (POD) 4,7,10 and 14 (n=5 per group in each POD) by percentage of wound closure.The mice was euthanized on POD 1,4,7,10,14,21,28 and 35 (n=1 in each POD).The wounds were removed,routinely fixed,paraffin-embedded,sectioned and HE-stained.A modified scoring system was used to evaluate the wounds.The results showed that acute inflammation peaked on POD 4 in non-thermal plasma group,earlier than in control group in which acute inflammation reached a peak on POD 7,and the acute inflammation scores were much lower in non-thermal group than in control group on POD7 (P＜0.05).The amount of granular tissue was greater on POD 4 and 7 in non-thermal group than in control group (P＜0.05).The re-epithelialization score and the neovasularization score were increased significantly in non-thermal group when compared with control group on POD 7 and 10 (P＜0.05 for all).The count of bacterial colonies was 103 CFU/mL on POD 4 and ＜20 CFU/mL on POD 7,significantly lower than that in control group (109 CFU/mL on POD 4 and ＞1012 CFU/mL on the POD 7) (P＜0.05).It was suggested that the non-thermal plasma facilitates the wound healing by suppressing bacterial colonization.