Although globozoospermia (round-headed spermatozoa) is encountered as 0.1% of the infertile population, familial appearance of globozoospermia is extremely limited. In this report, we aimed to describe two male siblings of 26 and 45 years of age with the clinical and pathological details of complete globozoospermia. Both light and electron microscopic examinations were performed for the diagnosis. Of note, the karyotype analyses of the two siblings revealed 46+ XY without any microdeletion on chromosome Y. In the available literature, there are only six more reports describing familial globozoospermia. Although association with several aneuplodies has been reported, specific numerical or ultra structural abnormalities in somatic or sex chromosomes have not been clarified. In this sense, the low incidence of the familial globozoospermia may be the primary cause of the failure to demonstrate any specific inheritance in such cases. However, documentation of siblings with globozoospermia may warrant strong and undetected genetic evidence for the pathogenesis of the globozoospermia.