Abstract: To determine whether the parasitic efficiency, fecundity and immature duration of parasitoids, Sclrodermus guani, would be enhanced by the previous experience with feeding on supplementary nutrition. S. guani was bred with the prepupa of Tenebrio molitor by directly inoculating female parasitoid in a tube. The effects of previous feeding experience from sucrose, fructose, glucose, or honey on host parasitization, parasitoid fecundity, and offspring lifespan of this species were investigated under laboratory conditions. The results indicated that sugar- rich foods could be the potential food resources for parasitoid S. guani. The parasitoids fed on sucrose, fructose, glucose, or honey had significantly higher parasitism rate on the prepupa of Tenebrio molitor than those only fed on distilled water. The parasitoids that previously fed on glucose or honey exhibited more fertility than those only fed on distilled water, fecundity of parasitoids which fed on sucrose or fructose honey had increase but insignificant difference compare with the others. However, the immature duration of parasitoids showed no significant difference among the treatments. These findings suggested that the process of nutritional supplements of parasitoid before encountering the hosts is vital. The effects of feeding on the four natural nutritional resources on the enhancement of parasitoid activity and fecundity are equivalent. The 10% glucose is the best source of nutrition used as supplementary food for the wasp adults.