The purpose of this research is to be grasp the relation between lumbago incidence rate and research hypothesis in the effects of sex life of the middle-aged couples in Taejon area upon lumbago. This writer had questionaired the 400 middle-aged couples in Taejon city - Jung-gu, Seo-gu, Dong-gu, Yuseong-gu, and Taedeok-gu - from June 1, to June 30, 1998. Of them, total 209 question papers were drawn back; male 102, female 107. Analysis of the data is as follows; 1. 145(69.37%) subjects of total 209 had low back pain experience after their sexual lives. 2. In the number of sexual times a week, low back pain incidence were the most rate in 1-2 times as 41.55%, each other had a statistically significant relation (P<0.01). 3. In age and lumbago incidence rate, the 30s was 37.75% and each other had a significant relation (P<0.05). 4. In weight and lumbago incidence rate, the level of 50kg~60kg was highest and each other didn't have a significant relation (P>0.05). 5. In the mean sexual time, the period of 11~20 minutes was 29.47% and each other had a significant relation (P>0.01). 6. In a day time of sexual life and lumbago incidence rate, midnight was the highest rate(36.23%) and each other didn't have a significant relation (P>0.05). 7. In the lumbago incidence rate according to bedroom structure of sexual life, a bed was 38.17% and each other had a significant relation (P>0.05). 8. In the lumbago incidence rate according to sexual posture, a normal position showed the highest rate(46.12%) and each other didn't have a significant relation (P>0.05). According to the results of our research, lumbago has relation to the number of sex life a week, age, the mean time of sexual life, and bedroom structure of sexual life. So it is thought that it is necessary that middle-aged couples periodically study the educational programs to make an prevention education for low back pain the key points.