Objective To observe the change regularity of IL-1?, IL-6, IL-10 and explore the mechanism of Yingfen syndrome (YS) in epidemic febrile diseases. Methods One hundred and four cases were divided into acute leukemia (AL) group and non-acute leukemia (NAL) group according to different diseases. According to syndrome differentiation of TCM, AL group was classified to 10 cases for Weifen syndrome (WS), 12 cases for Qifen syndrome (QS), and 20 cases for YS. NAL group was classified to 20 cases for WS, 24 cases for QS and 18 cases for YS. Fifteen healthy persons were selected for comparison. The levels of IL-1?, IL-6 and IL-10 in YS, WS and QS of various diseases were observed. Results In YS period, IL-1? and IL-6 increased continuously, while IL-10 decreased markedly, compared with healthy people (P 0.05), while on difference in IL-6, IL-10 between different diseases (P