Objective:To discuss the application of multiple seasonal ARlMA model to data in time series and fit predictive model on workload of inpatient department.Methods:Parameter of model is estimated using conditional least squares method according to the data of workload of inpatient department in a hospital in Chongqing from 2002 to 2005.The structure is determined according to criteria of residual un-correlation and concision.ARIMA predictive model was fitted and the order of model was confirmed through Akaike’s Information Criterion and Schwarz Bayesian Criterion.Results:Statistics assisted estimation of the model.The estimation of variance is 0.003 175

AIC=-94.245 1

SBC=-91.252 1.Using analysis of white-noise residual of mode1

fit of rich table show that the best estimated ARIMA model is(1-B)(1-B12)Zt=(1-0.543 02B)(1-B12)at.Conclusion:The model of ARIMA can be used to forecast for workload of inpatient department with high prediction precision of short-term time series.