What are the causes of erectile dysfunction? Erectile dysfunction can be caused by one factor or, more often, a combination of several factors. For a long time it was believed that in 90% of cases, erectile dysfunction is a psychological cause. We now know that 50% of cases are organic or physical (there are structural changes that cause this). However, it should be remembered that, although erectile dysfunction has a physical origin, from the moment the erectile dysfunction begins, psychological problems appear that support and often exacerbate the problem.