In order to investigate the law of ammonia volatilization and nitrogen infiltration in the process of biogas slurry surface application, the rules of ammonia volatilization of soil surface and the infiltration of total nitrogen, ammonia nitrogen, nitrate nitrogen and water in vertical soil profile were systematically explored by soil column experiments at room temperature. The experimental results show that the ammonia volatilization mainly happened in the first five days, which accounts for 97% of total amount. And the maximum daily ammonia volatilization is 93.24mg/(L〖DK〗·d), which appeared from the second day to the third day. The infiltration rate of ammonia nitrogen lagged behind the water infiltration. The distributions of water, ammonia nitrogen and total nitrogen mainly exist in 0~5cm soil. And the distribution area of nitrate nitrogen is 0~15cm, bigger than that of ammonia nitrogen. The variation of ammonia nitrogen of topsoil has a high to low trend. And the whole variant trend of nitrate nitrogen of topsoil is opposite to the ammonia nitrogen.