Background: Colorectal cancer (CRC) poses a significant public health burden worldwide. The investigation of the choice of medical facility among CRC patients is helpful for understanding access to health services and improving quality of oncology services to optimize health outcomes. However, there are limited studies on the topic. The objective of this study was to investigate the choice of medical facility and its associated factors among advanced CRC patients. Methods: This cross-sectional multi-center study included a total of 4,589 individuals with advanced CRC from 19 hospitals in 7 geographic regions in China. Participants were recruited by multi-stage stratified sampling. In the first stage, two cities in each geographic region were selected through simple randomsampling. In the second stage, one tertiary cancer hospital and/or one general hospital were selected in each city. Data on medical experience and demographics were collected via a questionnaire during face-toface interviews. Explanatory variables were selected based on the Andersen behavioral model. Multinomial logistic regression analyses were performed to explore the factors associated with the level of medical facility for the first treatment. Results: Hospitals at the prefecture level were the most common medical facility sought by advanced CRC patients for initial medical care (44.9%), the first definite diagnosis (46.3%), the first treatment (39.5%), and regular follow-up (38.9%). However, the first priority was changed to hospitals at the national level for the second treatment (38.0%) and after recurrence and metastasis (45.9%). Female {odds ratios (ORs) ranged from 1.31 [95% confidence interval (CI): 1.01-1.71] to 1.41 [95% CI: 1.07-1.87]} and relatively welleducated individuals [ORs ranged from 1.74 (95% CI: 1.20-2.53) to 7.26 (95% CI: 4.18-12.60)] preferred to seek higher-level health facilities. Individuals with metastatic CRC at diagnosis were more likely to visit hospitals in provincial capitals versus hospitals at the county level (OR =1.68, 95% CI: 1.27-2.22). Individuals with "good" health-related quality of life (HRQOL) (OR =0.63, 95% CI: 0.49-0.81) were less likely to seek hospitals at the prefecture level compared with hospitals at the county level. Conclusions: There is a need to improve the oncology services for CRC patients, including the optimization of referral reform policy and the promotion of quality of primary healthcare service. The results may provide evidence to fill the policy-implementation gap and potentially contribute to the improvement of the efficiency of the healthcare system.