Purpose <p>Although HIV is likely to be a couple-based issue among serodiscordant male couples due to cross-partner transmission, little is known about how they cope with HIV as a team. This study aimed to examine the dyadic coping process among serodiscordant couples.</p> Methods <p>A dyadic daily diary study was used to answer our research questions. One hundred and forty-one Chinese HIV serodiscordant male couples completed measures of we-disease appraisal, common dyadic coping, quality of life, and relationship satisfaction for 14 consecutive days and ART adherence, attitudes toward PrEP, quality of life, and relationship satisfaction at a 2-month post-diary assessment. Computations were based on the common fate mediation model, using multilevel structural equation modeling.</p> Results <p>Regarding direct effect, we-disease appraisal was associated with both partners’ quality of life at the between-person level, post-diary quality of life, attitudes toward to PrEP, relationship satisfaction at both levels as well as post-diary relationship satisfaction. Common dyadic coping mediated the association between we-disease appraisal and both partners’ quality of life as well as relationship satisfaction at the within-person level. However, no mediating effects were observed at the between-person level.</p> Conclusions <p>Our findings highlighted the importance of the daily dyadic coping process among HIV serodiscordant couples. Future interventions should direct resources toward fostering a shared disease appraisal and training couples in common dyadic coping strategies for their daily lives.</p>