Methyl benzimidazole carbamate (MBC) is a broad spectrum systemic fungicide effectively used against a wide variety of pests of vegetable crops and fruit orchards. On seed treatment MBC was found to be actively absorbed by the seedlings and transported to aerial parts. The residual activity of the chemical on various parts of vegetable and food crops was reported to vary from 3.5 to 6.3 ppm persisting from 15 days to 45 days in different parts of the plant. However, WHO has recommended the desirability of conducting short-term and long-term toxicity studies of this fungicide in mammals. Subsequent studies revealed its embryotoxic potential in rats and rabbits. This paper gives the results of sub-chronic administration of MBC in rats designed to assay the possible toxicity to vital organs like the haemopoetic system, liver and kidneys.