This study, based on grounded theory, explores the adaptational process of parents of pediatric oncology patients. Thirty-two Taiwanese parents (26 mothers and 6 fathers) were interviewed. Data were collected through individual in-depth and focus group interviews, observations, medical chart review, nurses' note, and researchers' reflexive journals. The findings suggest that parents adapt to their children's cancer by a dynamic process; i.e., they modify their coping tasks and related strategies as clinical events (e.g., diagnosis, side effects, relapses, or death) occur. This adaptational process consisted of five components: confronting treatment, maintaining family integrity, establishing support, maintaining emotional well-being, and searching for spiritual meaning. Related factors such as coping tasks are described.