Dry selfed seeds of Corchorus capsularis (jute), type D-154 were irradiated with different doses of x rays. For studies in growth chamber the doses 10,20,30,40 and 50 kR and for field experiments two doses 20 and 40 kR were used. The characters, namely, germination, flowering behaviour, pollen sterility and survivality of X/sub 1/ population were studied. The mutants viz., C.M. (creeping mutant) and D.M. (dwarf mutant) were isolated in X/sub 2/ generation from 20 kR treatment. The mutants were grown up to X/sub 5/ generation and were compared with the control D-154 for height, leaf shape, fibre cells and physical and chemical properties of fibre cells and it was found that the mutants were in no way better than the original mother type D-154 with regard to the characters observed.