With the rapid development of domestic rail transit, the demand for construction financial support will be huge. The operating railway lines is increasing as well, the demand for operation and maintenance funds will continue to increase. How to realize the sustainable development of rail transit will be a immediate problem. After 150 years of development, Japanese railway companies basically can achieve profitability. Taking Tokyo metropolitan area as an example, this paper analyzes the operation status and development path of three-level rail transit enterprises, finds that developing related business is the key to the sustainable development of Japanese rail transit. Through the analysis of business form and profit status of related business of Japanese railway companies,this paper finds that chinese rail transit can develop related business through the three stages of ‘real estate, retail and service, diversified business’, and combine the Japanese business model to practice the business mode of sustainable development.