Introduction:Erectile dysfunction (ED) has become a public health issue in Nigeria because of its increasing magnitude, association with chronic medical conditions and negative impact on sexual life.Materials and Methods:Cross-sectional study of 450 male patients aged 18-70years who presented with non-ED related complaints. Main outcome measurements were prevalence and severity of ED which was assessed with International Index of Erectile Function (IIEF-5) and single-item sexual function questionnaire. Also assessed were socio-demographic characteristics, physical activities, sexual satisfaction and morbidities.Results:The prevalence of ED was 55.1% (mild, moderate and severe were 32.6%, 17.8% and 4.7% respectively). Prevalence of ED was significantly associated with age (p < 0.0001), marital status (p = 0.032), income (p = 0.001), social class (p = 0.004), physical activities (p = 0.006) and BMI (p = 0.012). Prevalence of ED was significantly high among men with diabetes mellitus (72.7%), hypertension (70.7%), peptic ulcer disease (70.4%) and previous prostate surgery (76.2%). Logistic regression showed dissatisfaction with sexual life (OR = 0.689, CI = 1.233-5.866; p = 0.013) and having sexual activities less than desired (OR = 3.331, CI = 1.416-7.839; p = 0.006) to be the most significant factors associated with ED. There was a strong positive correlation between the IIEF-5 and single-item sexual function questionnaire (r = 0.747, p < 0.0001).Conclusion:The prevalence of ED is high among males attending a primary care clinic in Nigeria with non-ED related complaints. ED was more prevalent in men with chronic medical illnesses and sedentary lifestyle. Family physicians should inquire about this condition in these men and refer them early for specialist consultation.