The development and behavior of Epidinocarsis diversicornis (Encyrtidae), a parasite of Phenacoccus herreni Pseudococcidae) was studied. Developmental time was 35.72 at 20°C, 20.15 at 25°C and 18.12 at 30°C. The most favorable diet for rearing was sugar water which gave average longevity of 26.34 d el vs . The lover developmental threshold was estimated at 13.5°C and the physiological time for developm ent from egg to adult was 230.97°D (degree-day). The females of E. diversicornis H . reproduce by thelytokolous parthenogenesis and are able to parasitize all the stages of their host. Third instar nyrnphs and adult fe• males are prefered, however of first nyrnphs suffer the greatest mortality due to parasitizacion (13.22 olo). Second instar P. herreni, and third instar and adult females encapsulated 9.22 y 5.2 % respectively to the inmature stages of E. diversicornis.