Based on the land use maps in 1995, 2000 and 2010, as well as the statistical data of cropland use in Zhengning County of Gansu Province, cropland distribution change and cropland protecting pressure were studied before and after the "grain for green" project by using ENVI, ArcGIS and SPSS.After the "grain for green" project, most of low-quality slope croplands were returned to forestland, and some of high-quality plain croplands were occupied by expanding construction land.The spatial pattern of croplands changed from scattered and irregular to concentrated and regular distribution.Factors for cropland protecting pressure in Zhengning County can be divided into artificial, policy and natural factor.The artificial factor is mainly de-termined by people's living standards and crop production conditions, the policy factor is affected by restora-tion subsidy,and the natural factor is reflected by damage area of cropland.In order to relieve cropland pro-tecting pressure in the area where the "grain for green" project was implemented, more emphasis should be placed on protecting the existing plain cropland from being occupied by construction land, stabilizing a con-siderable ecological compensation level for avoiding reclamation of the returned cropland, and limiting agro-chemical inputs in order to reduce the risk of agricultural non-point source pollution?