OBJECTIVE The aim of this study was to determine the frequencies of Y chromosome microdeletions in infertile azoospermic and oligozoospermic Turkish men and in healthy control subjects. METHODS Sixty-four azoospermic and 51 oligozoospermic patients infertile patients, and 70 healthy men who had a child without the aid of assisted reproductive technologies were included in this study. DNA was extracted from peripheral blood samples collected from the patients. Following multiplex PCR performed with 15 different primer sequences, Y chromosome AZFa, AZFb, AZFc and AZFd region microdeletions were determined by agarose gel electrophoresis. RESULTS Y chromosome microdeletions were detected in 8 (12.5%) patients in the azoospermia group and 3 (5.9%) patients in the oligozoospermia group. The overall frequency of Y chromosome microdeletions in all infertile cases was 9.6%. Y chromosome microdeletions were not found in the healthy control group. Among the infertile cases, there were 4 (3.48%) AZFa, 2 (1.74%) AZFb, 3 (2.61%) AZFc and 7 (6.09%) AZFd region microdeletions. Y chromosome microdeletions were not found among healthy men in the control group. CONCLUSIONS The presence of Y chromosome microdeletions among azoospermic and oligozoospermic infertile males suggests that routine genetic testing and genetic counseling prior to the use of assisted reproduction techniques are necessary.