The article presents the data from recent literature and personal, practical experience of differential diagnosis of skin allergies in children. The difficulties detected at various stages of the disease diagnosis with the need for differentiation of allergic diseases (food allergy, atopic dermatitis, urticaria, insect allergy) and non-allergic genesis are: viral infections with skin lesions (herpes, chicken pox, measles, infectious erythema, hand foot mouth disease), bacterial infections of the skin (strep-and staphylodermia), and a group of other diseases (ichthyosis, scabies, psoriasis). It also should be mentioned that special emphasis on diagnosis belongs to food hypersensitivity, which combines immunological and nonimmunologic reactions. An example of the observation of 60 children with skin allergies shows the approach to the investigation of the diagnosis and the difficulties that arose during this. All children were ill for more than 3 months, and at the time of inclusion in the research, there were no identified causes of the disease. The diagnostic algorithm included three stages: clinical (detailed collection of complaints and anamnestic data), laboratory (general blood test, biochemical and coprological examination, determination of total IgE and specific IgE to gluten and different milk fractions, serological biomarkers of celiac disease) and instrumental. For 14 days before blood collection patients underwent an elimination test. 2 L. Besh et al. The results of the study showed that in the study group of children aged 1-5 years the main diagnosis was atopic dermatitis (36.84%), food allergy (24.56%), lactase deficiency (7.02%), helminthiasis (7.02%), streptodermia (5.25%), celiac disease (3.51%). The need for an individual approach to the laboratory-instrumental algorithm of skin allergies was described, and the results of our personal approach to the diagnosis were shown.