Purpose: Food insecurity, which is the inability to obtain food or inadequate food consumption in terms of quality and quantity, has physical and psychological consequences on children's health. This study aimed to investigate the relationship between children's growth disorders and food insecurity in Qazvin city, Iran. Methods: A case-control study was conducted on 177 cases and 355 controls of children aged 3 to 6 years, who were referred to health centers in Qazvin city. The case group consisted of children with growth disorders. Data were obtained with the 18-item US Department of Agriculture questionnaire, a household socioeconomic questionnaire, a and growth monitoring card. The data were analyzed with using IBM SPSS Version 22.0, by independent sample t-test, chi-square test, and logistic regression. Results: A significant relationship was found between children's growth disorders and household food insecurity with (p<0.05, odds ratio [OR]=17.0, confidence interval [CI]=5.9, 48.8) and without hunger (p<0.05, OR=2.69, CI=1.4, 4.9). There were also significant relationships between children's growth disorders and socioeconomic status (p<0.05, OR=3.4, CI=1.4, 8.5), the duration of breastfeeding (p<0.05, OR=0.94, CI=0.9, 0.98), and children's ages (p<0.05, OR=0.94, CI=0.92, 0.96). Sex and birth order, and the age of the parents was not found to be significantly related with growth disorders. Conclusion Lower socioeconomic status and household food insecurity were the important predictors of children's growth disorders. Policymakers should focus more on promoting steady employment and income among family members. Nutritional education for mothers is also recommended, in order to better meet the nutritional needs of the children.