IntroductionThe global burden caused by stroke is shifting to young and middle-aged people. Researchers have emphasised the significance of benefit finding (BF) in psychological health. However, current research has paid little attention to stroke and has discussed BF from only a single perspective, that is, that of either patients or caregivers. Our study aims to understand the changing trajectory, predictors and dyadic interaction of BF in dyads of patient who had a stroke and caregiver.Methods and analysisThis study is a longitudinal mixed-methods, multicentre study. A total of 142 patients who had a stroke and 142 spousal caregivers will be investigated. Participants will be recruited from four large public hospitals in northern China. Quantitative and qualitative data will be collected at five time points (near discharge and 1, 3, 6 and 12 months following discharge). Validated and reliable questionnaires will be used in quantitative studies. Information on sociodemographic data, BF, functional status, perceived stress, coping styles and mutuality will be collected from the dyads. Qualitative data will be collected via semistructured interviews and observations. The growth mixture model will be used to analyse quantitative data, and Colaizzi’s seven-step analysis method will be used to analyse qualitative data. We plan to conduct parallel but separate quantitative and qualitative data analyses and ultimately integrate the data sets to determine confirmation, expansion or discordance.Ethics and disseminationAll participants will be provided with an informed consent form. This study will encode all identifiable data and store all recorded data on a secure research server. This study has been approved by the Ethics Review Committee of the College of Nursing and Health, Zhengzhou University (ZZUIRB2020-53). The results of the longitudinal study will be published in peer-reviewed journals and presented at national conferences.Trial registration numberChiCTR2000039509.