Abstract: 【Objective】Explore the fertilization effect of oats in the northern Yinshan Mountain,and provide scientific basis for the rational fertilization of dryland oats in the northern Yinshan Mountain.【Methods】Based on the long-term positioning experiment（started in 2004）of Wuchuan dry farming experimental station in Inner Mongolia,the effects of different fertilization measures on oat yield,plant nutrient absorption and oat water and fertilizer utilization efficiency under long-term fertilization conditions were studied.【Results】Oat yield,1 000-grain weight,plant high,panicle length and spikelet number per plant could be significantly increased under the combination use of chemical and organic fertilizer（NPK+O） and balanced fertilization（NPK）.The grain yield under NPK+O and NPK conditions could be increased by 49.86% and 38.97% compared with oat planted without fertilization（CK）.The oat LAI,biomass,and amount of absorption of N,P,and K could be significantly increased under NPK+O and NPK treatments,the maximum LAI,and biomass were 2.62 and 6 066 kg/hm²,respectively.The max amount absorption of N,P and K was 115.28,26.77 and 132.92 kg/hm²,respectively.Combined application of NPK+O and NPK could significantly increase the water use efficiency in oats,reaching 8.17 and 7.84 kg/（hm²·mm）,respectively,which were 46.5% and 40.0% higher than CK.The use efficiency of N,P₂O₅,and K₂O under NPK was 36.37%,17.93%,and 59.92%,respectively.Each 100 kg oat absorbed N 3.38-6.21 kg,P₂O₅ 1.09-1.49 kg,K₂O 3.98-7.43 kg,with a value of 4.93,1.31,and 5.77 kg,respectively.【Conclusion】The combination use of chemical and organic fertilizer（NPK+O）and balanced fertilization（NPK）could significantly increase yield,nutrient absorbs,water and fertilizer utilization efficiency of oats,which were nutrient management models for high efficient resource utilization and oat yield increase.

Key words: Oat, Nutrient absorption, Yield, Water and fertilizer utilization efficiency, NPK, Oryanic fertilizer