Based on the survey data of 502 large planting households in the middle reaches of the Yangtze River,this paper analyzed the influencing factors and economic effects of the specialization of large planting households. The results showed that:(1) The average specialization index of the large planters was 81.04%,which was further illustrated by the higher specialization level of large planters in the study area and less types of planted crops; (2) The level of specialization of large planting households was significantly positively affected by age,participation in cooperatives and the distance from the village to the county yet negatively affected by Party membership,the proportion of household agricultural income,the area of cultivated land and multiple cropping index; (3) The higher degree of specialization downsized the profit per acre,but weakened the negative effect of labor input cost on the profit per acre. Accordingly,the government is not supposed to blindly advocate the transformation of large households to specialized planting under the current agricultural production conditions. The establishment and improvement of supporting facilities to agricultural specialization is the premise to the specialized development of farmers under the condition of improving regional industrialization level.