Objective: To analyze the spatio-temporal distribution characteristics of new HIV/AIDS cases at ages of 50 years and older in Wenzhou City from 2006 to 2020, so as to provide insights into precise control of AIDS. Methods : The data of new HIV/AIDS cases aged 50 years and older in Wenzhou City from 2006 to 2020 were collected from the China Information System for Disease Control and Prevention. The temporal and spatial distribution characteristics of new HIV/AIDS cases at ages of 50 years and older were identified using global and local spatial autocorrelation analyses and spatial-temporal scan analysis. Results: Totally 1 917 new HIV/AIDS cases aged 50 years and older were detected in Wenzhou City from 2006 to 2020, and there were 179 new HIV/AIDS cases in 58 townships ( streets ) from 2006 to 2010, 643 cases in 113 townships ( streets ) from 2011 to 2015 and 1 095 cases in 147 townships ( streets ) from 2016 to 2020, respectively. The distribution of new HIV/AIDS cases appeared positive spatial autocorrelations from 2006 to 2010 ( Moran's I value=0.05, Z=1.976, P=0.046 ), from 2011 to 2015 ( Moran's I value=0.08, Z=2.314, P=0.028) and from 2016 to 2020 (Moran's I value=0.18, Z=3.956, P=0.003 ). Spatial-temporal scan analysis identified two clusters. The primary cluster mainly covered 70 towns ( streets ) in Lucheng Distrct, Ouhai District, Longwan District, Economic and Technical Development Region, Rui' an City and Pingyang County of Wenzhou City from January 1, 2014 to December 31, 2020, with a cluster radius of 34.30 km [log likelihood ratio ( LLR )=192.84, RR=2.60, P<0.001], and the secondary cluster was located in Hongqiao Township of Yueqing City from January 1, 2009 to December 31, 2015, with a cluster radius of 0 ( LLR=90.60, RR=7.27, P<0.001 ). Conclusions The number of new HIV/AIDS cases aged 50 years and older appeared a tendency towards a rise in Wenzhou City from 2006 to 2020, with spatial clusters that were predominantly identified in urban areas, Rui' an City and Pingyang County of Wenzhou City.