Because little is known about how low-income Latino and African American men attribute meaning and adapt to prostate cancer treatment-related symptoms relative to masculine identity, in this study we sought to develop a descriptive model of this process. Using qualitative methods, 60 Latino and 35 African American/Black men were interviewed by language- and ethnicity-matched male interviewers using a semistructured guide. Interviews were audiotaped and transcribed verbatim. Spanish transcripts were rigorously translated to produce English transcripts. Analysis using grounded theory techniques found that men constructed masculine identities that were influenced by early experience, challenged by several factors including prostate cancer treatment, and underwent a renegotiation process that resulted in the maintenance of their identity as men. Development and testing of interventions that support this process will facilitate the adaptation process for men in a culturally relevant manner.