Objectives: This paper reports the findings of two studies that examined factors predicting infertility distress in male partners within couples with an infertility diagnosis and where the couple was receiving fertility treatment. Design: A cross-sectional design was implemented using a questionnaire battery (The questionnaire battery comprised an inventory of four different standardised questionnaires compiled together into one booklet) compiled from earlier theory-building qualitative research conducted by the authors. Methods: Infertility related distress was examined in relation to a number of psychosocial variables including relationship dynamics, self-esteem, current mental health and attitudes towards idealised masculinity. The questionnaire battery was completed by 167 men undergoing or consulting for fertility treatment. Participants were recruited through Irish fertility clinics (Study 1, n = 111) and through an online survey (Study 2, n = 55). Results: Regression analyses identified four variables that predicted variance in infertility distress in both studies: 'Attitude towards idealised masculinity', 'Mental health', 'Relationship satisfaction' and 'Self-esteem'. This finding was found to be robust having controlled for age, time since diagnosis, number of attempts at treatment and diagnostic category (male factor, female factor or mixed factor infertility). Conclusion: Recommendations for fertility clinics and mental health professionals should be made in relation to managing infertility distress and supporting couples during fertility treatment.