In the longterm structural health monitoring for largescale steel reinforced concrete structure , the creep and shrinkage effect must be considered .Otherwise it can cause inaccurate or wrong results. The modification on the original data from strain senors can improve the monitoring precision. The influence of creep and shrinkage on the engineering project was studied. Then using the data from the Guangzhou New TV Tower structural health monitoring system, how to use the method from ACI to predict the creep and shrinkage was explained. Finally, a specific project example for Guangzhou New TV Tower was used to verify that the modified strain can fit the theoretical strain very well and has higher reliability.