We examined the nutritional value of different diets on the longevity and reproductive performance of black soldier flies (Hermetia illucens) under laboratory conditions. In addition to water only (W) (control group), four diets were used: sugar and water (SW); pollen, sugar, and water (PSW); pollen, honey, and water (PHW); and honey and water (HW). The PSW group exhibited the highest reproductive performance because it had the longest oviposition period, largest number of clutches and hatched clutches, largest number of eggs laid/female, and greatest male and female longevity. Nevertheless, the highest hatching rate was found in the SW group. The number of successfully hatched eggs (fertilized) was the greatest in the PSW and HW treatments, but the differences between diets (SW, PSW, PHW, and HW) were nonsignificant.