--- - |2+ Abstract Objective This study examined the course and predictors of supportive care needs among Mexican breast cancer patients for different cancer treatment trajectories. Methods Data from 172 (66.4% response rate) patients were considered in this observational longitudinal study. Participants were measured after diagnosis, neoadjuvant treatment, surgery, adjuvant treatment, and the first post‐treatment follow‐up visit. Psychological, Health System and Information, Physical and Daily Living, Patient Care and Support, Sexual, and Additional care needs were measured with the Supportive Care Needs Survey (SCNS‐SF34). Linear mixed models with maximum‐likelihood estimation were computed. Results The course of supportive care needs was similar across the different cancer treatment trajectories. Supportive care needs declined significantly from diagnosis to the first post‐treatment follow‐up visit. Health System and Information care needs were the highest needs over time. Depressive symptoms and time since diagnosis were the most consistent predictors of changes in course of supportive care needs of these patients. Conclusions Health system and information care needs of Mexican breast cancer patients need to be addressed with priority because these needs are the least met. Furthermore, patients with high depressive symptoms at the start of the disease trajectory have greater needs for supportive care throughout the disease trajectory. - Psycho-Oncology, Volume 27, Issue 9, Page 2132-2140, September 2018.