Optimism and mastery are two cognitive traits that involve positive expectations for the future and that have been demonstrated to be important predictors of reduced anxiety as well as superior coping and physical health in many populations, including cancer survivors. There is limited research, however, examining the unique effects of these traits when examined simultaneously. The present cross-sectional study used structural equation modeling to examine the unique effects of optimism and mastery on emotion, coping, and health in 603 adult cancer survivors, and whether results were consistent in men and women. Results indicated that both optimism and mastery were associated with improved emotion, coping, and health and together accounted for a small to moderate amount of variance. Although the effects of optimism were generally greater, mastery also uniquely predicted most dependent variables and there was some evidence that gender influenced these effects, with optimism predicting health control more so in women and mastery predicting health control more so in men. These results demonstrate that it is important to examine both generalized positive expectancies such as optimism and positive expectancies regarding mastery when investigating resilience and emotional well-being in cancer survivors.