Skin cancer presents a significant public health burden in Australia. The present study aimed to supplement population-based estimates of sun protection behaviour by examining setting-specific trends in directly observed sun protection in public outdoor leisure settings. Repeated cross-sectional observational surveys of adolescents and adults were conducted on summer weekends between 11 am and 3 pm from 1992 to 2002, 2006 to 2012, and 2018 to 2019 (N = 44,979) at pools/beaches and parks/gardens within 25 km of the centre of Melbourne, Victoria. The primary outcome was a binary index representing individuals having above or below the median level of body surface covered by hat, shirt, and leg garments in each setting type. The prevalence of above-median body coverage increased between 1992 and 2002 in both settings. At pools/beaches, a slight decline in above-median body coverage between 2006 and 2019 in males and females (adjusted odds ratio, AOR = 0.96 [0.94, 0.97]; 0.94 [0.93, 0.95]) appeared to be driven by a decline in leg coverage, while arm coverage, hat, sunglasses, and shade use remained stable. At parks/gardens, a decline in above-median body coverage between 2006 and 2019 (AOR = 0.90 [0.89, 0.91]; 0.94 [0.93, 0.95]) was accompanied by small declines across other protective behaviours that varied between males and females. Patterns in protective behaviours observed in outdoor leisure settings may reflect the changing composition of individuals choosing to remain outdoors during peak UV times and highlight the importance of continued promotion and monitoring of the use of multiple measures to protect against UV damage in Australia. [ABSTRACT FROM AUTHOR]