Abstract: OBJECTIVE To undertake clinic investigation into the infection rate， season， age， area of children's acute upper respiratory tract infection caused by parainfluenza virus in clinic and to study treatment based on syndrome differentiation by TCM patent medicine. METHODS We collected 1090 cases with children's acute upper respiratory tract infection in the city of Ji`an， Shenyang and Nanjing from April 2009 to January 2011， of which 973 remained after falling off and rejecting. After syndrome differentiation， they were divided into two groups through center stratiform and interval. The control group (487 cases) were given ribavirin; while the treatment group were administrated by TCM patent medicine for three days as a course. The parainfluenza virus was detected to observe the therapeutic effect of the patent medicine and its related influential factors. RESULTS The infection rate of this virus was 5.65%， spring is the season with high concurrency， the city of Nanjing and Ji`nan are the highly infection area， and also the infection of parainfluenza virus is not confined to one type. CONCLUSION Parainfluenza virus is one of the most common viruses causing children's acute upper respiratory tract infection; the infection rate is of a close relation with season and location; treatment based on syndrome differentiation by TCM patent medicine is stable and feasible.