The silkworm breed. NB4D2 fed on varied types and age groups of mulberry leaves during late-age in different seasons (winter, summer and monsoon) recorded significant differences with regard to grainage performance. Feeding silkworms with tender mulberry leaves during winter found superior in recording pupal weight (15.99g/10), fecundity (553.00 eggs/laying) and hatchability (94.27%), whereas medium leaves fed during winter recorded higher rate of pupation (83-50%) and moth emergence (82.75%). However, the larvae received soiled leaves during summer found least (9.11g/10, 325.75 eggs/laying, 85,43%, 49.50%, 47.00%, respectively).