Globally, it has been reported that 38% of people live in areas with iodine deficiency and are at risk of its complications. The main health concern of iodine deficiency during pregnancy is its negative effect on the brain and nervous system of unborn infants. Despite the national availability of iodized salt was 89%, adequate utilization of iodized salt is only 41.9%. Hence, this study was to assess utilization of iodized salt and factors associated among pregnant mothers in Kimbibit District. Community based cross-sectional study design was conducted. Simple random sampling technique was used to select a total sample of 555 pregnant mothers. Single population proportion formula and Stat. calc software were used to calculate the required sample size. Data were collected using interview administered pretested questionnaire and iodized salt test kit. Collected data were entered using Epi info 7 and then exported to SPSS 20 for further analyses. Descriptive statistics were used to describe important variables and binary logistic regression was used to identify candidate independent variables. P< 0.05 was used for testing significance and AOR with 95%CI was used to identify the strength of association between dependent and independent variables. From the total respondents, 48.1% (95%CI: 44.1%, 52.1%) of them adequately use iodized salt. Mother with formal education (AOR, 2.46; 95%CI: 1.70, 3.56), urban residents (AOR, 1.80; 95%CI: 1.14, 2.93), purchasing from open markets (AOR, 0.35; 95%CI: 0.23, 0.50), storing at sun light (AOR, 0.24; 95%CI: 0.13, 0.45) and storing more than two months (AOR, 0.64; 95%CI: 0.42, 0.98) were independent factors significantly affect adequate utilization of iodized salt. Utilization of iodized salt was low compared to the standard. Mother's education, residence, place of purchase, place of storage and duration of storage were independent factors which significantly affect adequate utilization.