The paper studies organic mineral complex component and distribution character of organic carbon of black soil under various cultivation pattern.The results showed that organic mineral complex in black soil primarily compose by the silt organic mineral complex,the organic carbon in black soil primarily consist in the small granule diameter of organic mineral complex,there is a accumulation tendency for organic carbon to the small granule diameter of organic mineral complex,as the black soil are cultivated.The contents of organic carbon different fractions in black soil is decreasing and the ratio of HA and FA is increasing,with increasing of the granule diameter of organic mineral complex,and the smaller the particle size of complex,the greater the proportion of HA.Reclamation may cause the soil complex scattered and not conducive to cementing material HA category to arabica complexes distribution,crop rotation is conducive to the soil organic carbon accumulation of soil physical properties and the improvement of soil fertility improvement.