Based on an in-depth analysis of the data collected in the third national agricultural census in Beijing，this study finds that major changes have taken place in the basic structure and basic elements of rural communities in Beijing：the village size has further enlarged，and half of the rural population lives in large villages with more than 3000 people；the proportion of migrant population accounts for 45.69% of the residents in each village，10% higher than the ratio resulted from the second survey；nearly half of the rural population in Beijing live in the “invertedly populated village” where the migrant population exceeds the registered population；and the employment in the tertiary industry in rural areas in Beijing has reached nearly 2/3 of the total. In order to adapt to the above structural changes of rural communities，Beijing Municipality should speed up the process of integration of urban and rural governance，and actively explore a new path of social governance in rural areas around mega cities.