Background Food allergy is a component of the atopic march and may have effects on asthma. This study aimed to evaluate the risk factors for confirmed immunoglobulin E-mediated food allergies and their impact on the clinical picture in preschool children with asthma. Methods Clinical history and allergic assessment results were obtained from medical records and analyzed retrospectively. Preschool children with asthma were included in the study and the characteristics of food allergy and asthma were evaluated. The patients were grouped as those with food allergy (Group I, n = 60) and those without (Group II, n = 98). Results In patients with food allergy and asthma, the number of episodes requiring systemic steroids in the last year (p = 0.002), atopic dermatitis (p = 0.001), parental atopic disease (p = 0.009) and aeroallergen sensitivity rates (p < 0.001) was higher than patients without food allergies. The use of medium or high doses of inhaled steroids to achieve asthma control was more frequent in patients with food allergies (p = 0.014). Parental history of atopic disease [p = 0.007, odds ratio (OR): 3.27, 95% confidence interval (CI) 1.37-7.77)], atopic dermatitis (p = 0.017, OR: 2.80, 95% CI: 1.19-6.57), starting complementary food after 6 months (p = 0.004, OR: 3.9, 95% CI: 1.5-10.0) and having aeroallergen sensitivity (p < 0.001, OR: 6.01, 95% CI: 2.21-16.29) were identified as significant risk factors for food allergy. Conclusion Asthmatic preschool children with food allergies are more likely to have a parental atopic disease, atopic dermatitis, aeroallergen sensitivity and starting complementary food after 6 months. These patients experience more asthma attacks and need higher doses of steroids.