Evidence shows that adolescent and young adult (AYA) cancer patients have an increasing survival rate but experience psychological distress and circadian rhythm dysregulation. Little is known about the effect of circadian rhythm on psychological distress. To investigate the type of circadian rhythm in Chinese AYA cancer survivors and examine the associations among chronotype, demographic characteristics, psychological distress, anxiety and depression, character strengths, and medical coping in this group. This cross-sectional study enrolled 800 AYA cancer participants, 728 of whom completed the Chinese version of the Morningness-Eveningness Questionnaire, the Distress Thermometer, the Hospital Anxiety and Depression Scale, the Three-Dimensional Inventory of Character Strengths, and the Medical Coping Modes Questionnaire. Evening- and morning-type participants accounted for 35.0% and 19.1%, respectively, among participants, which was significantly higher than those found in the general population. The prevalence of psychological distress was 84.9% among AYA cancer participants. Exercise, Distress Thermometer, and depression were important predictive factors for the circadian rhythm. Circadian rhythm disorder and psychological distress were common among AYA cancer survivors. Evening-type participants performed worse on character strength, confrontation, and avoidance of medical coping. Healthcare professionals need to understand the circadian rhythm and psychological health of AYA cancer survivors. Psychological rehabilitation guidance, especially within the 6 months after diagnosis, may benefit AYA survivors according to their chronotype. Character strengths can also be used during rehabilitation to properly guide AYA survivors.