Abstract: Lining of hydraulic tunnel is the main component of tunnels,and it works together with surrounding rocks to support loading,and then enhances the stability of surrounding rock. How to model the performance of the lining of the hydraulic tunnel is worth discussing. By taking a hydraulic tunnel in a water diversion project as an example,a hybrid model of steel bar stress meter is put forward for the lining of hydraulic tunnels based on in-situ data. The model is composed of internal water pressure,temperature and timing component. And internal water pressure is calculated by structure formula,temperature and timing are acquired by statistics. Therefore,measured stress is well reflected by fitting curves,correlation coefficient of R6 and R5 between fitting value and measured value is 0.987 and 0.861 for inner and outer steel bar stress respectively. Furthermore,monitoring warning value for inner and outer steel bar stress is preliminarily established. Above all,hybrid model put forward herein can be used for monitoring the change of lining of hydraulic tunnel,and provide reference for the operation of projects.