Red degeneration of myoma has been very scarcely reported whereas there have been many case reports regardiog myoma uteri complicated by pregnancy. The rate of myoma uteri complicated by pregnancy runs 0.3%+7.2% accordiog to the statisrics. Statistics based on our experience indicates, however, a little bit lower rate 0.2%. Red degeneration of myoma is mors frequently accompanied by pregnancy than non-pregnancy, which would be well backed up by Campbell`s report 56% to 76% for the former, 7% through 10% for the latter. this is a big difference. It is interesting in these cases that red degeneration appeared without marked change in size of myoma uteri. It will be also observed etiologically as the nonpregnancy myoma uteri.