A 43-year-old man came to our clinic complaining of infertility and semen analysis showed azoospermia. Analysis of chromosomes showed a mosaic 45, XO/46, X, ＋mar1/46, X, ＋mar2 karyotype, and the marker chromosomes were considered to be two kinds of ring Y chromosomes. Y chromosome microdeletion analysis showed partial deletion of Azoospermic Factor (AZF) a, and complete deletion of AZFb and AZFc. The patient gave up having a child because these results indicated that no sperm would be collected even if Testicular Sperm Extraction (TESE) were performed.