The aim of the study was to find whether personality traits of men with Klinefelter syndrome and their partners (group 1-n = 17) differ from those of couples affected by idiopathic infertility (group 2; n = 16) and from those of fertile couples (group 3 n = 17). We further investigated the attitudes of the three groups towards pregnancy, labour and sexuality to find potential différences among the three groups. Besides, we verified the hypotheses of below average or low average intelligence of men with Klinefelter syndrome, and of inferior quality of social life in these men. The data were collected using the interview on medical history, the questionnaire on attitudes towards pregnancy, labour and sexuality (S-S-G), the personality questionnaire MMPI-2. The Raven progressive matrices were used only in group 1. The results show that men with Klinefelter syndrome and their partners do not differ significantly from the couples with idiopathic infertility (group 2), having some shizoide traits in their personality structure and mostly negative attitudes towards pregnancy, labour and sexuality. However, a significant difference has been found between the Klinefelter syndrome group and the fertile couples group. The hypothesis of below average intelligence has not been confirmed, but the quality of social life of men with Klinefelter syndrome has been found inférior. We may thus conclude that in the management of infertile couples in whom the man has been affected by Klinefelter syndrome, the personality structure, importantly affecting the outcome of treatment, should be taken into consideration.