Abstract: The commercially available nutrient yeast salt medium (NYSM) was compared with the low cost and locally available media for the production of mosquito larvicidal bacteria Bacillus sphaericus strain GC IV in the laboratory. B. sphaericus strain GC IV was produced using egg yolk, soybean flour, coconut water and banana pulp as growth media and their mosquito larvicide efficacy was compared with the same bacteria produced in NYSM as reference medium. B. sphaericus GC-IV cultured in egg yolk medium produced 100% Culex quinquefasciatus larval mortality (p = 0.0035, df = 1, χ2 = 8.53) at LC90 dose of reference NYSM medium, whereas the total bacterial biomass production was high in soybean flour medium (p<0.0001, df = 4, F= 66.83). The overall cost ratio obtained by considering medium cost and mosquito mortality obtained in all the media used favoured the egg yolk medium. The egg yolk provided a low cost yet efficient medium for culturing the B. sphaericus GC IV strain, therefore, it can be used for the large scale production of the mosquitocidal bacterial strain. The present study emphasizes the use of potential and cost effective growth media for mosquitocidal bacteria production in integrated vector control programmes.