Tactile sensitivity of the penis is related to sexual functioning, however its role in diabetic erectile problems is unclear. We evaluated penile sensitivity in 10 diabetic men with erectile dysfunction, 17 sexually functional diabetic men and 14 control subjects. Finger and penile thresholds and ratings of intensity and pleasantness for finger and penis were assessed using vibrotactile stimulation. Glycosylated haemoglobin and total and bioavailable testosterone measurements were determined and subjects completed self-reports on sexual function. Diabetic men with erectile problems had higher values of glycosylated haemoglobin than sexually functional diabetic men (p = 0.02) and both groups had lower bioavailable testosterone than control subjects (p< or =0.05). Sexually dysfunctional diabetic men had a higher finger threshold than the other two groups (p<0.01). Penile threshold for the sexually dysfunctional group was also marginally higher compared with the functional diabetic group (p<0.052) but did not differ from control subjects (p = 0.09). Diabetic men with erectile dysfunction exhibited different response patterns than sexually functional men on dimensions of intensity and pleasantness to penile stimulation. Although these data do not directly implicate subjective response to penile stimulation in diabetic erectile problems, they suggest such anomalous response could be one contributing factor.