By use of the month-by-month hospital admissions caused by asthma and the influenza and month-mean pressure,temperature,and humidity data in Nanjing,the occurrence regularities of the two diseases were discussed.Two time serial models including meteorological factors were established to predict the number of patients on a monthly basis.Results show that in the recent 10 years,hospital admissions caused by asthma increased year after year and asthma is prone to occur at autumn and the end of spring.The occurrence of asthma is correlated with the mean pressure of the same month and the mean temperature of previous month.However,the influenza is more likely to occur in summer and autumn and its occurrence is related to the month mean minimum temperature and the month's lowest temperature.The conditional heteroskedasticity model and ARIMAX model were established to predict the number of patients caused by asthma and influenza,respectively.The prediction veracities for asthma and influenza are 75.5 percent and 66.7 percent,respectively,which indicates that the methods are feasible and applicable in application.