BACKGROUND: The objective of this study was to determine how patient preferences guide the course of palliative chemotherapy for advanced colorectal cancer. METHODS: Eligible patients with metastatic colorectal cancer (mCRC) were enrolled nationwide in a prospective, population-based cohort study. Data were obtained through medical record abstraction and patient surveys. Logistic regression analysis was used to evaluate patient characteristics associated with visiting medical oncology and receiving chemotherapy and patient characteristics, beliefs, and preferences associated with receiving >1 line of chemotherapy and receiving combination chemotherapy. RESULTS: Among 702 patients with mCRC, 91% consulted a medical oncologist; and among those, 82% received chemotherapy. Patients ages 65 to 75 years and aged ≥75 years were less likely to visit an oncologist, as were patients who were too sick to complete their own survey. In adjusted analyses, patients aged ≥75 years who had moderate or severe comorbidity were less likely to receive chemotherapy, as were patients who were too sick to complete their own survey. Patients received chemotherapy even if they believed that chemotherapy would not extend their life (90%) or that chemotherapy would not likely help with cancer-related problems (89%), or patients preferred treatment focusing on comfort even if it meant not living as long (90%). Older patients were less likely to receive combination first-line therapy. Patient preferences and beliefs were not associated with receipt of >1 line of chemotherapy or combination chemotherapy. CONCLUSIONS: The majority of patients received chemotherapy even if they expressed negative or marginal preferences or beliefs regarding chemotherapy. Patient preferences and beliefs were not associated with the intensity or number of chemotherapy regimens.