Post-stroke depression (PSD) can aggravate the mortality and recurrence rate in stroke patients. The relationship between family functioning and PSD at different phases after a first-ever stroke is unclear. The purpose of this longitudinal study was to investigate the patterns and relationship of family functioning and PSD at acute hospitalization and 6 months post-discharge in first-ever stroke survivors.This is a longitudinal study conducted in Guangzhou, China. Family functioning and depression were measured by the Short Form Family Assessment Device (SF-FAD) and Self-Rating Depression Scale (SDS) at baseline and 6 months post-discharge. Multiple linear regression analysis was used to explore the relationship between family functioning and PSD.The prevalence of PSD at acute hospitalization and 6 months post-discharge was 32.9% and 20.0%, respectively. SDS scores decreased significantly from baseline to 6 months post-discharge, while SF-FAD scores did not change significantly during this period. The Pearson correlation coefficient showed that SF-FAD scores were positively associated with SDS scores at the two time points (r 1 = 0.341, r 2 = 0.510, P < 0.05). Multiple linear regression analyses indicated that SF-FAD scores could predict PSD at baseline (unstandardized coefficient: 7.010, P < 0.05) and 6 months post-discharge (unstandardized coefficient: 9.672, P < 0.001).This study found that first-ever stroke survivors had good family functioning at baseline and 6 months post-discharge. The findings in this study verified that poor family functioning is positively associated with PSD at different phases post-stroke. Good family functioning is an important protective factor against PSD.© 2022 Wang et al.