This study examined the nutritional status of mothers in one of the most populous food-insecure zones in southern Ethiopia, the Sidama zone. The study used primary data collected from 1094 households with a child under 24 months located in ten kebeles (the smallest administrative district). Households were selected using multi-stage probability sampling techniques. The mothers' nutritional status was estimated using both body mass index (BMI) and mid-upper-arm circumference (MUAC). The results from the BMI analysis revealed that 28.1% of the women were malnourished (BMI <18.5) and 67.5% were normal (BMI 18.5 to <25.0), while the remaining small proportion (4.5%) fell in the overweight or obese categories. Similarly, the computation of maternal nutritional status by MUAC analysis showed that 31.4% of the women were malnourished (MUAC <22). Further analysis of the main predictors of maternal malnutrition using logistic regression showed that three individual-level variables and three household-level variables predicted maternal malnutrition: woman's age, duration of breast-feeding, literacy status, marital form, land size and intra-household food distribution. The study concludes that maternal malnutrition is a serious problem in the study area and that there are contextual risk factors that could be addressed to partially tackle the problem.