Abstract Purpose Health-related quality of life (HRQoL) measurement represents an important outcome in cancer patients. We describe the evolution of HRQoL over a 5-year period in colorectal cancer patients, identifying predictors of change and how they relate to mortality. Methods Prospective observational cohort study including colorectal cancer (CRC) patients having undergone surgery in nineteen public hospitals who were monitored from their diagnosis, intervention and at 1-, 2-, 3-, and 5-year periods thereafter by gathering HRQoL data using the EuroQol-5D-5L (EQ-5D-5L), European Organization for Research and Treatment of Cancer’s Quality of Life Questionnaire-Core 30 (EORTC-QLQ-C30), and Hospital Anxiety and Depression Scale (HADS) questionnaires. Multivariable generalized linear mixed models were used. Results Predictors of Euroqol-5D-5L (EQ-5D-5L) changes were having worse baseline HRQoL; being female; higher Charlson index score (more comorbidities); complications during admission and 1 month after surgery; having a stoma after surgery; and needing or being in receipt of social support at baseline. For EORTC-QLQ-C30, predictors of changes were worse baseline EORTC-QLQ-C30 score; being female; higher Charlson score; complications during admission and 1 month after admission; receiving adjuvant chemotherapy; and having a family history of CRC. Predictors of changes in HADS anxiety were being female and having received adjuvant chemotherapy. Greater depression was associated with greater baseline depression; being female; higher Charlson score; having complications 1 month after intervention; and having a stoma. A deterioration in all HRQoL questionnaires in the previous year was related to death in the following year. Conclusions These findings should enable preventive follow-up programs to be established for such patients in order to reduce their psychological distress and improve their HRQoL to as great an extent as possible. ClinicalTrials.gov Identifier: NCT02488161