Two field experiments were carried out to to evaluate the effect of microbial - compost (MC) on high yielding rice cv. OM6976 planted on alluvial soil of Song Hau farm, Co Do district, Can Tho city and Cuu Long Delta Rice Research Institue, Thoi Lai district, Can Tho city, in cropping winter - spring season, 2011-2012. The results showed that grain yield of 1 ton MC/ha plus 50 N - 30 P2O5 - 15 K2O kg/ha treatment did not differ with grain yield of 100 N - 60 P2O5 - 30 K2O kg/ha treatment. On the other hand, analysis of economical effect showed that applying MC together with half quantity of inorganic fertilizer in rice was the highest income. Therefore, application of MC not only saved a half concentration of chemical fertilizers for rice cultivation but also supported rice plants having good lodging resistance, this led to increase yield component and protein content in rice - seed but soil fertility of MC treatment did not change in comparison with initial soil fertility.