Abstract: In this research six economical characteristics in seven lines with Chinese and Japanese origin and their hybrids were studied. The results showed that the General Combining Ability (GCA) of Japanese lines was significant for all the characteristics (p<0.01), while GCA of Chinese lines for resistance characteristics were insignificant and for productive characteristics were very significant (p<0.0001). In Japanese lines GCA of the number of survived larvae and pupae and also the percentage of pupa survival in line101433 were 14.84, 34.55 and 10.65, respectively. These were higher than other groups. The highest GCA of mentioned characteristics in Chinese lines was for line Koming 1 and they were 5.86, 9.00 and 2.82, respectively. Specific Combining Ability (SCA) for productive characteristics and the number of survived larvae was considerable (p<0.05) and for the number of survived pupa and the percentage of pupa survival was insignificant. SCA of resistance characteristics in the hybrid of Xihang 1xKoming 1 were 18.41, 21.62 and 5.00, respectively which were higher than others. Chinese lines have high resistance and low genetic diversity for resistance characteristics and Japanese lines have low genetic divergence and high mean of resistance characteristics. Increasing non-additive genetical variance of cocoon characteristics show high efficiency of heterosis on above characteristics, in a way that the percentage of heterosis of productive characteristics, especially the cocoon shell weight, was higher than the percentage of heterosis obtained in resistance characteristics.