The causes of infertility vary widely and differ between regions and within countries. There is no report on this subject in Morocco. Therefore, the aim of this study was to determine the causes of infertility in Moroccan infertile couples and to compare the findings with data from the various published studies. This retrospective study included 1265 infertile couples who attended the Assisted Reproductive Technology Unit of the Reproductive Health Centre of the University Hospital Ibn Sina in Rabat. All couples had been infertile for at least 1 year and both partners were fully investigated. The median duration of infertility was 5 ± 4 years. Couples had primary and secondary infertility in 77.2% and 22.8% of cases, respectively. Among the 1265 couples, 39.6% had a female factor, 28.2% had a male factor, 17% had both male and female factors and in 15.2% of couples, the cause of infertility was undetermined. The most common causes of male infertility were varicocele (14.3%), obstructive azoospermia (7%), Congenital anomalies (5.5%) and male accessory gland infection (4%). Results showed that 54.8% of men had a normal semen analysis. Among women, infertility factors were ovulatory disorders (27.5%), tubal factor (26.6%), uterine factor (12.6%), endometriosis (4.1%), and 43.4% of women were normal. The causes of infertility in this study are comparable with those reported by the World Health Organization and other studies. However, the substantial delay before attending an infertility clinic highlighted by the study needs additional consideration.