Objective: Insight into trajectories of positive affect (PA) and negative affect (NA) across the cancer continuum may improve understanding of the nature of adjustment problems. The primary aim of this study was to identify subgroups of patients with distinct trajectories of PA and NA following diagnosis of colorectal cancer (CRC). Secondary to this aim, the co-occurrence between trajectories and their association with goal-related processes was explored. Method: CRC patients (n = 186) completed questionnaires within 1 month, 7 months, and 18 months after diagnosis. Multilevel models were used to study the trajectory of PA and NA, as measured with the Positive and Negative Affect Schedule (PANAS). Results: Four classes with distinct PA trajectories were identified: low (18.8%), increasing (6.7%), moderate (68.2%), and high (6.3%); 2 trajectories of NA emerged: low (36.3%) and moderate (63.7%). There was no significant association between PA and NA trajectory class probabilities. The average trajectory of PA covaried with levels of goal disturbance and goal reengagement over time, while the average NA trajectory covaried with goal disturbance and goal disengagement. Conclusions: Compared with the general population, our sample of cancer patients suffered from a lack of positive emotions, but not a high presence of negative emotions. About one fifth of patients reported low PA up to 18 months after diagnosis and may benefit from supportive care. Furthermore, the trajectory of PA was independent of that of NA and related with a distinct goal adjustment process (i.e., goal disengagement vs. goal reengagement). This finding indicates the need to tailor psychological care to the nature of the adjustment problem.