One-fourth of pregnancies are either unwanted or mistimed in Bangladesh.Unwanted births not only pose risk to child health and wellbeing but also force to rapid population growth in resource strapped countries. The objectives of this study are to examine the extent of unmet need for contraception in Bangladesh and to explore the differentials in unmet need by some selected characteristics of the reproductive aged women in rural-urban Bangladesh. This study utilizes BDHS 2004 data. Chi square test and logistic regression analysis are used here. The total unmet need for family planning among currently married women in Bangladesh is found to be 12%. Unmet need to space births in rural area is higher than in urban area. The significant predictors of unmet need for spacing and limiting births are found to be ever using family planning, discussing family planning matters with spouses, number of living children, intention to have last child, age and education in the rural area whereas, age, intention of having last child, ever use of any contraception and discussing family planning matters with spouses in urban area. Rural women especially young married women deserve special consideration because unmet need to space birth is highest among them.