This paper uses descriptive statistics and a mixed linear model to explore the social -ecological factors affecting the hospitalization expenses of cross-provincial cancer patients to understand the influencing factors of their hospitalization expenses based on the framework of social ecology theory. The results showed that patients with malignant tumors of digestive organs in cross-province medical treatment were the highest among sampled population（18.66 %），with the highest average hospitalization cost of tumors found in patients with uncertain or unknown dynamics（45 535.24 yuan）. The hospitalization expenses were influenced by tumor types，personal behaviors like the length of hospitalization days in personal behavior，the distance of medical treatment at the environmental level，and the actual reimbursement ratio at the policy level（P < 0.05）. The hospitalization cost of cancer patients in different provinces was relatively high，which was affected by many social and ecological factors. It is necessary to analyze the influencing factors of hospitalization expenses from both the individual perspective of cross -province cancer patients and the ecological environment in which they live，to rationally allocate health resources and guide patients to seek medical treatment in order.