Abstract: Objective:To analyze the application of a new safe adult musculus vastus lateral injection (proportion method).Methods:Two hundred patients were divided into the traditional treatment group and the proportion treatment group according to the musculus vastus lateral injection provided by literature.The application safety zone and side effect were analyzed contrastively.Results:The irritative musculus vastus lateral inferior neuroligic symptom was present of the 8 cases of traditional treatment group,while the neurological symptoms of vascular injury was not confirmed in proportion treatment group.It was more difficult to determine the safety zone in the traditional treatment group,especially which in the female patients was significantly smaller.The traditional treatment group in which appearred sclerosis and pain impacting the movement was significantly higher than the proportion treament group (P<0.01),however there were not abscesses and other serious infectious complications in both groups.There were no apparent contracture of muscle necrosis in the traditional treatment group and the proportion treatment group.Conclusions:The best safety zone (abducting legs,between above 2/5 and the below 1/5 in the lateral thigh region) of the proportion method group is accurate and easily mastered.In the safe zone (abducting legs,lateral thigh below 3/5 regions),increasing 1.0-1.2 cm of the injection depth of the skin and superficial fascia thickness is safe.The proportion method can reduce the induration,pain and infection complications.