Recurrent infections seem to be a common complaint in children who are referred to general practitioners and pediatricians offices. Detection of primary immunodeficiencies (PID) etiology is very important for achieving appropriate diagnosis and treatment of these patients. The absence of appropriate treatment could lead to subsequent complications, in a hospital inpatient and/or outpatient settings. This study was performed in a group of children with recurrent infections to identify patients with underlying PID. A cross-sectional study was designed to evaluate the final clinical diagnosis obtained in 100 pediatric patients with a history of recurrent infections referred to Children s Medical Center, Tehran, Iran, during one year (2011-2012). History taking and physical examination, complementary laboratory tests including immunological investigations were done to confirm the main causes of disease according to our previously published stepwise approach to recurrent infections. Among all studied patients, 21% (11 males and 10 females) were diagnosed to have PID. Parental consanguinity (p = 0.001) and soft tissue infections (p = 0.004) were significantly higher in PID group, comparing to other causes of recurrent infections. Gender and location of infections were also linked to the type of PID including antibody deficiency, combined immunodeficiency and phagocytosis disorders. The real rate of PID as a cause of recurrent infection appears to be much higher than what is generally considered in a se-lected group of pediatric patients; so, following the suggested stepwise guideline can im-prove timely diagnosis and appropriate treatment of these patients.