The basic characteristics of initial wave and the determination method of the first wave height of landslide surges under current condition are studied by means of the 3D model test system of wave induced by granular rock landslide in curved shallow water area. According to the observation data of physical model test，we calculate statistically the maximum wave height，maximum period，effective wave height，effective period and wave steepness characteristic values of initial surge，analyze the effects of landslide angle，landslide volume，river depth and current velocity on the height of the first wave，and give the calculation formula of head wave height by using dimensionless and multiple regression analysis. Using the measured data of surge wave in Xintan landslide of the Yangtze River，we compare the formulas given in this paper with Noda formula，Slingerland formula，Pan Jiazheng formula，Yin Kunlong formula and formula of China Institute of Water Resources and Hydropower Research，and come to the conclusion that the difference between the calculated and measured values in this paper is the least.