Men with prostate cancer often need social support to help them cope with illness-related physiological and psychosocial challenges. Whether those needs are met depends on receiving support optimally matched to their needs. This study examined relationships between perceived stress, prostate cancer-related stigma, weak-tie support preference, and online community use for social support in a survey of online prostate cancer community participants (n = 149). Findings revealed a positive relationship between stigma and perceived stress. This relationship, however, was moderated by weak-tie support preference and online community use for social support. Specifically, stigma was positively related to perceived stress when weak-tie support was preferred. Analyses also showed a positive relationship between stigma and perceived stress in those who used their online community for advice or emotional support. Health communication scholars should work collaboratively with diagnosed men, clinicians, and online community administrators to develop online interventions that optimally match social support needs.