Purpose: Hepatitis C virus (HCV) cure after treatment with direct-acting antivirals (DAAs) can improve health-related quality of life (HRQoL). However, specific groups with chronic HCV may still exhibit worse post-cure HRQoL because of persisting severe liver fibrosis or social vulnerability factors (e.g. unhealthy alcohol use, living in poverty). We assessed the effect of such factors on longitudinal measures of HRQoL in chronic HCV patients. Methods: ANRS CO22 HEPATHER is a prospective cohort of chronic HCV patients receiving DAAs, which included notably patients with social vulnerability factors, a population usually under-represented in clinical trials. Multivariable mixed-effects linear regression models helped identify factors associated with longitudinal measures of HRQoL (PROQOL-HCV scores). Results: At enrolment, 52.4% of the 2740 participants were men, median age was 56 years [interquartile range 50-64], and 21.5% had severe liver fibrosis (FIB-4 > 3.25). Twenty-eight per cent reported current or past unhealthy alcohol use [> 2(3) alcohol units per day for women (men)], and 28.1% were living in poverty (standard of living under 1015€/month per household consumption unit). At first PROQOL-HCV completion, 54.0% of patients were HCV-cured. After multivariable adjustment, people with current or past unhealthy alcohol use, individuals living in poverty, those with severe liver fibrosis, and women had worse HRQoL in the dimensions explored. Conversely, HCV cure was associated with better HRQoL. Conclusions: Specific socially vulnerable groups of patients with chronic HCV infection still experience impaired HRQoL, independently of HCV cure. Patient-centred interventions, including social support and referral for comorbidities, should be prioritized for them. Trial registration with ClinicalTrials.gov NCT01953458.