Aim: Patients, who were being followed up for the last 10 years by Pediatric Immunology unit of the Faculty of Medicine at Erciyes University, were evaluated retrospectively in order to contribute toward the early diagnosis and the treatment of patients with humoralimmunodeficiency.Material and Methods: 412 patients with humoral immunodeficiency were evaluated retrospectively. Patients’ age, gender, consanguineous marriages, family history of immune deficiency or similar diseases were studied at the time of complaints and diagnosis.Results: Humoral immune deficiency was found among 412 out of 536 (76.8%) patients, who were being followed up because of primary immune deficiency. Although the average age of patients at the time of diagnosis was 48.9±4.6 months, the average age was 28.6±33.4 months at the start of complaints. Transient hypogammaglobinemia of infancy was observed the most among patients (50.5%), followed by IgA deficiency (28.4% ), hypogammaglobinemia (6.8%), IgA +IgM deficiency (3.6%), IgG subclass deficiency (3.2%), Common variable immunodeficiency (2.4%), Bruton disease (1.2%), and hyper IgM syndrome (0.5%) respectively. IVIG replacements were given regularly to patients who were diagnosed with either hypogammaglobinemia, CVID, Bruton disease and hyper IgM.Conclusions: In patients with recurrent infections, we need to certainly consider immune deficiency diseases first. Also, we need to be aware of the fact that humoral immune deficiency would relatively be diagnosable and treatable in most of these diseases. Finally,we need to educate the public about the role of marriages among relatives in order to decrease the frequency of these diseases.