The influence of cocoon cooking conditions on the cocoon filament exfoliation tension has been studied using cocoons from Indian and Japanese bivoltine hybrids. It was observed that the cocoon cooking conditions had a significant influence on the cocoon filament exfoliation tension. The exfoliation tension of undercooked cocoons was observed to be higher than that of moderately cooked cocoons and overcooked cocoons. A similar trend was observed also with the influence of cocoon cooking conditions on the moving standard deviation of exfoliation tension of cocoons from both Indian and Japanese bivoltine hybrids. Furthermore, changes in filament exfoliation tension from outer layers to inner layers were analysed. The occurrence of abnormal increase in exfoliation tension (due to hard agglutination points) was decreased from outer layers to inner layers in the case of Indian bivoltine hybrids CSR10×CSR11, whereas it was increased from outer layers to inner layers in the case of Japanese hybrid. This may be attributed to the racial characteristics of cocoons, spinning conditions and sericin.