Background: Vector distribution influences arbovirus persistence. This study examined the diversity of mosquito breeding sites in an Atlantic Forest fragment in Rio de Janeiro, Brazil. Methods: Mosquito specimens were collected at Fazenda dos Cordeiros, Silva Jardim, Brazil. Tire, plastic, bamboo, and sapucaia traps were evaluated for oviposition preferences using ecological indices. Results: Tire traps had the highest density. Bamboo traps showed the highest diversity. Plastic container was the most divergent site. The key recorded vector species included Aedes albopictus and Haemagogus leucocelaenus. Conclusions: Identifying the breeding sites that contribute the most to mosquito density is essential for optimizing control strategies.