The paper used methods of empirical formula and measured fitting to calculate channel leakage per kilometer in Henan province people's victory irrigation district.Taking the lateral canal as control unit,it calculated the canal seepage and canal head flow of different level canals from bottom to top in different plans.It analyzed water efficiency of irrigation based on spatial distribution by using the method of multiple regression analysis and obtained the suitable method of spatial distribution of water efficiency that is suitable for the irrigation area.The result can provide technical means and technical support for the transformation of canal irrigation water from different lateral canal to canal head.