Abstract: Abstract: The southwest karst region of China is the key and difficult area for rural revitalization. In view of the conditions and problems faced by the rural revitalization of the southwestern karst region, the paper discusses the relationship between urban and rural development and the path, mode and countermeasure of rural revitalization in the southwestern karst region of China. The result shows that: 1) On the basis of the existing urban system, a new type of mountainous urban system with small cities, small towns, key towns and central villages as the main body will be built to increase the urbanization rate and reduce the number of rural population and villages, and to a certain extent, improve the integration of urban and rural areas and realize the rural revitalization. 2) To achieve the deep integration of urban and rural economic development, the new mountainous characteristic urban system and agricultural modernization transformation is the core. On the basis of reducing the number of rural population and rural, we will realize agricultural modernization transformation with the multiple intensification, improve agricultural labor productivity, promote the deep integration of rural economy and urban economy, enable agricultural production to better share the fruits of economic development, ensure farmers' income is not lower than the average income level of migrant workers, and form a "endogenous" driving sustainable development mechanism of rural revitalization.3) On the specific path selection of rural revitalization: first, combined with the characteristics of karst mountain, we will focus on the implementation of new mountain characteristic urban construction projects, optimize the existing urban system through construction of small cities, small towns, key towns and central villages, fully realize local urbanization, enhance the radiation drive of towns, and promote the integration of urban economy and rural economic. Second, carrying out the multi-intensive agricultural modernization transformation of "labor and technology and capital", improve unit land productivity and unit labor productivity, resolve the contradiction between "small production" and "big market" of rural agriculture in the southwestern karst region, realize the close relationship between rural economy and market economy, leave agricultural profits in rural villages, to improve the link between rural economy and market economy, to leave agricultural profits in rural areas, and ensure the continuous increase of farmers' income. Third, implement of the construction of vertical and horizontal extension industrialization of karst mountain-specific agriculture. Through the integration of agricultural product strains and production supply and marketing, the vertical industrialization of agriculture is extended. Relying on historical and cultural villages, ethnic villages or production bases of characteristic agricultural products, etc., through rural tourism, agricultural tourism integration project or rural pastoral complex project, to achieve the horizontal industrialization of agriculture, agricultural production and economic development of the deep integration, to achieve the horizontal industrialization of agriculture, promote the deep integration of agricultural production and economic development, to achieve the development of agricultural endogenous drive, and finally achieve the endogenous sustainable development of rural revitalization. 4) In terms of rural revitalization support policies, we should start from the following aspects: First, according to local conditions, scientific planning, to build a reasonable new urban and rural system in southwest karst mountain. Second, innovate the agricultural management system and give full play to the leading agricultural enterprises and large agricultural households. With agricultural cooperatives, "companies and farmers", land circulation, land trusteeship and other modes of operation, achieve the organic convergence of farmers' agricultural production and market, to ensure farmers' income and stimulate the vitality of farmers. Third, strengthen rural intelligence and talent support; improve the level of scientific and cultural level of farmers. Fourth, innovate the rural land use and management system mechanism, invigorate rural land resources, and activate the bidirectional of urban and rural factors. Fifth, further improve the supporting role of infrastructure to ensure the transformation and revitalization of rural development.