Tehran University of Medical Sciences Journal of Arthropod-Borne Diseases 2322-1984 17 2 2023 09 13 1401 1401 Desca Tyagnes-Hanindia District Health Office of Demak District Government, Central Java Province, Indonesia, Undergraduate School in Public Health Science, Faculty of Public Health, Universitas Muhammadi-yah Semarang, Semarang, Indonesia Didik Sumanto Undergraduate School in Public Health Science, Faculty of Public Health, Universitas Muhammadi-yah Semarang, Semarang, Indonesia, Laboratory of Epidemiology and Tropical Diseases, Faculty of Public Health, Universitas Muham-madiyah Semarang, Semarang, Indonesia Sayono Sayono Undergraduate School in Public Health Science, Faculty of Public Health, Universitas Muhammadi-yah Semarang, Semarang, Indonesia 2021 01 04 2023 08 27 Background: Reduction of the Aedes aegypti population is the priority effort to control dengue virus transmission in­cluding the use of larvivorous fish. Biologically, the predatory efficiency of fish will slow down when the water acidity and temperature change from normal conditions. This study aimed to determine the predatory efficiency of three species of larvivorous fish against the Ae. aegypti larvae in different water temperatures. Methods: Three well-known species of larvivorous fish namely Poecilia reticulata, Betta splendens, and Aplocheilus panchax were placed into 12 cm diameter jars with three water temperature ranges namely 20–21 ºC, 27–28 ºC, and 34–35 ºC, and allowed to three days acclimatization. As many as one hundred 4th-instars larvae of Ae. aegypti were gradual­ly entered into each jar, and a longitudinal observation was made at 5, 10, 30, 60, 120, 240, 360, 480, 600, and 720 minutes. The predated larvae were recorded. Results: In normal temperature ranges, the predatory efficiency of the larvivorous fish was 75%, 72.3%, and 32.8% for B. splendens. Aplocheilus panchax, and P. reticulata, respectively. The predation abilities decreased due to temperature changes. Betta splendens and A. panchax indicated the best predatory efficiency against Ae. aegypti larvae in different temperature conditions. Conclusion: Betta splendens is the best larvivorous fish in the lower to normal, but A. panchax is the best in the normal to higher temperature ranges. This finding should be considered by public health workers in selecting larvivorous fish to control the Dengue vectors. https://jad.tums.ac.ir/index.php/jad/article/view/1401 https://jad.tums.ac.ir/index.php/jad/article/download/1401/622