The purpose of this study is to identify the relation between functional limitation, functional disability and back pain during pregnancy. Data was collected by interview or self-report from 66 pregnant women between the gestational ages of 17 and 22 weeks who had experienced back pain from February 17 through July 28, 2001. The results of this study are as follows; 1. The prevalent mean week of back pain starting during pregnancy was 12.8. The mean pain intensity scores on the VAS during the past week and now were 5.6 and 3.7. The mean score on the functional limitations was 38.9. The mean score on the functional disability was 19.7. 2. The pain intensity on the past week was correlated with the pain intensity now (r=.339, p<0.01) and the functional limitations (r=.251, p<0.05). The pain intensity now was correlated with the functional limitations (r=.295, p<0.05) and the functional disability (r=.429, p<0.01). The functional limitations was correlated with the functional disability (r=.229, p<0.01). The higher pain intensity was the more functional limitation and functional disability occurred. 3. There was a statistically significant correlation between the pain intensity now and the type of housing (t=-2.051, p=.045), and back pain history before pregnancy (t=-2.429 p=.003). 4. There was a statistically significant correlation between the functional limitation and income (F=2.803, p=.047) and back pain history before pregnancy (t=-3.225, p=.002). There was a statistically significant correlation between the functional disability and back pain history before pregnancy (t=-3.058 p=.003). In conclusion, we found that a history of back pain was an important factor when predicting back pain and functional disability and limitation during pregnancy. The nurse and the prenatal educator should detect risk factors of back pain early in pregnancy and manage continuously though pregnancy.