Objective：To discuss the optimal frequency of external application of split-bone ga uze for relieving swelling after Colles fracture.Methods：Selected 60 case of patients with Colles fracture，and divided them into two groups randomly.Both groups receivedmanual reduction combined with splint fixation and external application of split-bone gauze.The experiment group 1 received the instillment of split-bone gauze every two days and the replacement of split-bone gauze once a week，while the experiment group 2 received the replacement of split-bone gauze once a week without the instillment of split-bone gauze during the treatment.Both groups received treatment for 4 weeks.Measured the palm circumference at the healthy and affected side and recorded the differences of the palm circumference at normal and lesion side.Results：All the cases reached the clinical healing standard of fracture within 6 to 8 weeks.Before treatment，the palm circumferences in both groups were compared，difference being not significant(P ＞ 0.05)；after treatment，adopted repeated measures analysis of variance to compare the palm circumferences at various observation time points，and the intragroup comparison at each observation time point was made，differences being significant(P＜ 0.01)；in comparison between two groups，differences showed significant(P＜ 0.01)，which indicated the differences of palm circumferences in both groups were decreased as the treatment time increased，and the experiment group 1 was better than the experiment group 2.Conclusion：When Colles fracture is treated with manual reduction combined with splint fixation and external application of split-bone gauze，it is of more significant effect to instil split-bone gauze once in two days than replace split-bone gauze once a week without the instillment of split-bone gauze in the duration so as to relieve swelling.