This study was undertaken to elicit barriers and knowledge gaps regarding the benefits of family planning among women in Irrua, Edo State, Nigeria. Using a cross-sectional design, a structured questionnaire was administered to 180 consenting women attending antenatal clinic sessions in a large hospital. The control of family size, 72/180 (40.0%) and child spacing, 64/180 (35.6%) were the major benefits of family planning stated. The most direct benefit to maternal health - absence of pregnancy complications - was the least mentioned (5%). A total of 18/180 (10.0%) stated that family planning w as of no benefit. No statistically significant association was demonstrated between educational levels and the knowledge of family planning benefits. Respondents aged 30 - 49 years were more likely than the younger ones to state child spacing as a benefit of family planning methods [logistic regression: p = 0.004; OR = 2.61 (95% CI = 1.37 - 4.98)]. The commonest reasons for objecting to family planning were the fear of infertility, 28/114 (24.6%), incom plete family size, 24/114 (21.1%), side effects of contraceptives, 19/114 (16.7%) and partners’ objection, 17/114 (14.9%). This study demonstrates important knowledge gaps with respect to family planning benefits. T his could reflect poor knowledge delivery or uptake on family planning. The findings suggest that women’s knowledge and experiences regarding family planning are crucial to interventions on fertility control. Overall, the study shows that the identified knowledge gaps and barriers reflect opportunities for holistic interventions including needs-sensitive health education for males and females on family planning.