Introduction: Frequent infection is located in the first place among the reasons for the application polyclinic in infancy and pre-school. The aim of this study is to evaluate the insidence of allergic disease in patients who apply to our allergy-immunology clinic for frequent infectious diseases and diagnosed with immunoglobulin isotype deficiency. Material-Method: The medical records of 2592 patients who have complaint of frequent infection attended to Department of Pediatric Immunology-Allergy, *** University School of Medicine between January 2013 and February 2016 were investigated as retrospectively. Results: 258 (9.9%) of the patients had immunoglobulin isotype deficiency. Age range was 6-204 months. 151 (58.5%) were male, 107 (41.5%) were female. 17% had parental consanguinity. The diagnosis of patients: 12 (4.6%) selective IgA deficiency, 31 (12%) partial IgA deficiency, 53 (20.5%) isolated IgM deficiency, 117 (45.3%) transcient hypogammaglobulinemia of infancy. 33 (12.7%) considered as prolonged hypogammaglobulinemia and 12 (4.6%) unclassified hypogammaglobulinemia. 173 (67%) patients had an allergic disease besides immunoglobulin isotype deficiency diagnosis. The allergic diagnosis of patients were; 90 asthma, 66 atopic dermatitis, 47 allergic rhinoconjunktivitis and 44 transcient wheezing of infancy. There was no statistical difference between isotypes about co-insidence of allergic disease and immunoglobulin deficiency (p=0.83). Conclusion: Rate of accompanied by an allergic disease regardless of the type of immunoglobulin isotypes deficiency had been high in our patients. Keep in mind and investigate surely of immunodeficiency may be combined with recurrent infection and atopy in patients whom admitted with allergy symptoms is important for appropriate management of treatment.