[Objective] This paper tries to predict the daily number of theft activities. [Methods] We used LSTM network to analyze theft data from a large city in north China. First, we retrieved our data from January 1, 2005 to February 24, 2007 and from January 1, 2009 to January 7, 2011, respectively. Then, we set three different cases to examine the time series prediction of the daily number. Finally, we compared our results with those of ARIMA,Support Vector Regression, Random Forest and XGBoost with the same data set. [Results] The percentage root mean square error(PRMSE) of our model were 18.4%, 11.7% and 41.9%, respectively, which were better than those of ARIMA, Support Vector Regression, Random Forest or XGBoost model. [Limitations] More research is needed to predict the period when the number of theft crimes fluctuates dramatically. [Conclusions] The proposed model could improve the decision makings for community safety, police patrol and other specific missions.