Small and medium-sized cities are not only an important support for the development of big cities，but also an important platform for urban-rural integration. Using the relevant data of small and medium-sized cities in China from 2015 to 2019，this paper analyzes the current situation and existing problems of urban-rural integration of small and medium-sized cities in China from the aspects of population integration，economic integration and spatial integration. The research shows that China’s urban-rural population integration is developing in fluctuation，and the degree of economic integration and spatial integration is strengthening. At the same time，there are some problems，such as insufficient population integration，inefficient allocation of urban and rural resource elements，infrastructure construction to be improved，and large differences in urban-rural integration among regions. On this basis，through the analysis and comparison of urban-rural integration development cases of Tongzhou District of Beijing，Sanhe，Dachang and Xianghe counties and cities in Hebei，urban-rural integration development in Japan and other small and medium-sized cities at home and abroad，the study puts forward the following suggestions：Taking unified planning as the guide，institutional innovation as the breakthrough，infrastructure as the starting point，and industrial integration as the foundation Take population integration as the core and public services as the focus.