Unmet needs show the gap between ideals and reproductive behavior of women. This article aims to evaluate and examine the determinants of the need among married Kurdish women of 15-49 in Mahabad. This research was conducted through the data of fertility survey in March 2012, in Mahabad with a sample size of 700 families. According to the results the rates of unmet needs for birth intervals and child bearing stoppage, and unmet needs to use modern ways of pregnancy prevention are respectively 10.85 and 9.85 percent and the total rate of unmet needs is 20.7 percent. Women’s worry about side effects of pregnancy prevention means is the most important reason for avoiding pregnancy prevention. Social and cultural limits such as husband’s and other family members’ disagreement, as well as religious reasons come next. Findings of the study are in agreement with Bhushan and Bollato’s theories. Considering determinant role of some cultural characteristics as well as economical and social ones and factors related to family planning to predict the possibility of any unmet needs for family planning, it is recommended to undertake some comparative studies through component method in areas which are heterogeneous in terms of ethnos and culture in order to evaluate the unmet needs of family planning and to find the influencing factors.