Silkworms are an alternative feed to grow and develop for fish seeds. Silkworms have the advantage of being high in nutrients. The purpose of this study was to determine the effect of using fish offal silage combination feed on silkworm biomass and population as well as the optimal concentration of fish offal silage and fermented rice bran to increase silkworm biomass and population. The method used in this study was experimental using a completely randomized design (CRD), namely P0: paddy mud, P1: paddy mud + combined feed (75% fish offal silage and 25% fermented rice bran), P2: paddy mud + combined feed (50% fish offal silage and 50% fermented rice bran), and P3: paddy mud + combined feed (25% fish offal silage and 75% fermented rice bran). Data analysis used Analysis of Variance (ANOVA) and continued with Duncan’s test. The results showed that silkworm cultivation using a combination feed (25% fish offal silage and 75% fermented rice bran) produced the highest absolute biomass and absolute population of 22 grams and 7,147 individuals, significantly different from absolute and absolute biomass. produced from cultivation in paddy field mud with control treatment.