In order to analyze the dynamic characteristics of hydraulic torque converter applied to wheel loader,firstly,the original steady performance of hydraulic torque converter was discovered through a bench test.Second- ly,the V-shaped shovel and transport operations of ZL50 wheel loader were tested.Then,on the basis of test data,the distributions of engine torque were analyzed.Moreover,a mathematical model of hydraulic torque converter was established according to Newton's law of motion and used to investigate the dynamic characteristics of hydraulic torque converter in the two above-mentioned working conditions.Finally,a comparison is made between the dyna- mic test values of torque ratio and the static ones.The results show that the dynamic performance of torque converter can be replaced by the steady one when wheel loader is in transport condition.However,as the fluctuation range of angular acceleration is too large in V-shaped shovel operation，the dynamic characteristics must be considered.