PurposeDepression is one of the most common mental disorders and substantially decreases socioemotional well-being and health-related quality of life. Analyzing temporal patterns in depressive symptoms can reveal emerging risks that require attention and have implications for mental health promotion. The present study disentangled age, period, and cohort (APC) effects on trends in depressive symptoms and their gender disparities among China's nationally representative samples of middle-aged and older adults.MethodsUsing four-wave data (2011, 2013, 2015, and 2018) from the China Health and Retirement Longitudinal Study (N = 65455), APC effects were quantified based on the hierarchical APC model. The 10-item Center for Epidemiologic Studies Depression Scale (CES-D-10) was used to measure depressive symptoms.ResultsDepressive symptoms increased during late life and stabilized after reaching an advanced age. After further adjusting for individual characteristics, depressive symptoms exhibited a negative trend with advancing age. The mean levels of depressive symptoms remained stable during the study period. Depressive symptoms varied significantly across cohorts, with those born in 1949-1951 having the most severe depressive symptoms. Significant life-course and cohort variations existed in the gender gaps in depressive symptoms. Although women had higher mean scores on the CES-D-10 scale throughout the life course, the gender gaps in depressive symptoms gradually narrowed with age, as depressive symptoms decreased more rapidly among women. A widening trend in gender gaps in depressive symptoms was found among those born after the mid-1950s, mainly driven by a notable decline in depressive symptoms among menConclusionsThe convergence of living conditions between genders in late life, as a result of traditional Chinese culture, may have narrowed the gender gap in depressive symptoms. However, given the widening gender disparities in depressive symptoms among younger cohorts, more attention should be paid to women's mental health in the context of China's rapid socioeconomic development.