Some lung cancer patients after surgical treatment die as a result of pneumonia or cardiac failure without recurrence of lung cancer months or years after surgery because many such patients are aged or have decreased lung function. Surgical treatment may be partly to blame for these deaths. In this article, to evaluate the contribution of surgical treatment to deaths resulting from other disease, we calculate predicted survival rates using abridged life tables and compute relative survival rates. From 1952 to 1985, a total of 1289 lung cancer patients underwent surgical resection of lung cancer in our department. We calculated some kind of survival rates according to age, stage, and operative procedure. Each case was classified according to age (5-year periods), year of operation (5-year periods), and sex. The 5-year survival rate indicated by the abridged life tables in each class was regarded as the 5-year predicted survival rate of the case. The mean of 5-year predicted survival rates of all cases in a group was regarded as being the 5-year predicted survival rate of the group. The ratio (actual survival rate of the group/predicted survival rate of the group) was also calculated. The ratio of the patients who had stage O, I, or II diseases tended to decrease according to age. This fact supposed that the number of deaths resulting from other diseases with no recurrence of lung cancer in which surgical treatment contributed to death increased in the elderly. In the other hand, this tendency did not exist in the patients who had stage IIIA diseases.