The hyper-IgM syndrome is a rare primary immunodeficiency disorder caused by genetic mutations. It is characterized by recurrent infections with decreased IgG and IgA levels, but normal or elevated IgM levels in the serum. We describe the case of a 29-year-old female with a history of recurrent bacterial infections since childhood. Laboratory findings showed abnormal serum immunoglobulins, IgG 640 mg/dl (reference range: 825-1,852 mg/dl); IgA 47 mg/dl (reference range: 91-385 mg/dl); and IgM 420 mg/dl (reference range: 11-185 mg/dl). But blood B-cell count was normal. These findings were compatible with the diagnosis of hyper-IgM syndrome. Additionally, bronchial asthma was diagnosed at the age of 15 year; thereafter asthmatic attacks occurred frequently. We describe the characterization of hyper-IgM syndrome and the association between low levels of serum IgA and bronchial asthma.