To evaluate the safety and efficacy of vardenafil in primary care, we undertook a post-marketing surveillance study in 384 men with erectile dysfunction (ED), enrolled by 22 family physicians in Korea, from July 2004 to August 2005. Of the 384 patients enrolled, 343 (89.3%) returned for efficacy assessment and safety evaluation. Among the latter, 279 patients (81.3%) reported that their erectile function improved, 292 (92.1%) showed enhanced IIEF (International Index of Erectile Function)-5 scores and 265 (77.9%) responded that they were 'very satisfied' or 'satisfied' with vardenafil treatment. The most frequent reason for patient satisfaction with vardenafil was erectile potency (62.4%), followed by safety (42.4%), rapid onset (35.3%), adequate duration of efficacy (28.5%) and easy administration (25.9%). A total of 23 adverse events were observed in 18 patients, with the most frequent being hot flushes (3.2%), followed by headache (1.2%), nasal congestion (0.6%), color vision disturbance (0.3%), dizziness (0.3%), dry mouth (0.3%), dyspepsia (0.3%), nausea (0.3%) and diarrhea (0.3%). Only one patient discontinued vardenafil as a direct result of an adverse event. These results suggest that vardenafil prescribed by primary care physicians improved erectile function and was well tolerated by patients with ED.