The aim of the study was to assess the relation of knowledge score for cesarean disadvantages and selecting the mode of delivery. In this cross-sectional study, we studied 192 women who referred to obstetrics and gynaecology clinics in Jahrom, Iran. All women and their fetus were healthy without any problems and were in the third trimester of first pregnancy. We used a questionnaire including demographic situations and eighteen questions about disadvantages of cesarean section. The data recorded with using SPSS version 15 and analyzed by chisquare, independent t-test and one-way ANOVA test. Mean knowledge score was lower among mothers that intend to do cesarean section than those selected vaginal deliveries (10.82 ± 4.46 vs. 12.50 ± 4.08, respectively) that there was significantly different (P= 0.025). The most common reason for choosing cesarean section was fear of vaginal delivery (n= 24, 61.6%). The mean knowledge score was higher women who selected cesarean section in comparison to ones selecting vaginal delivery. Thus an important step is providing better information to pregnant women about modes of delivery, their indications, advantages and adverse consequences.