Objective To compare and assess the efficacy of ventral/dorsal onlay graft urethroplasty in the treatment of urethral stricture. Methods We searched pertinent English literature via MEDLINE (1966 to 2007), EMBASE (1977 to 2007) and The Cochrane Library (Issue 4, 2007) for the use of ventral/dorsal graft urethroplasty in the reconstruction of urethral defect associated with urethral stricture. Data were extracted by two reviewers independently and analyzed by SPSS 13.0 software. Results A total of 50 studies involving 1 264 patients were included. Ventral onlay graft urethroplasty was used in 751 patients with a success rate of 82.6%, while dorsal onlay graft urethroplasty was used in 513 patients with a success rate of 86.9% (ventral vs. dorsal, χ2=4.432, P=0.035). Oral mucosa graft had the highest success rate (88.1%) of all grafts, and the success rate of free skin graft onlay urethroplasty was associated with the location of graft placement (ventral vs. dorsal, P=0.016). Concerning the location of stricture, urethroplasty for bulbar urethral stricture achieved the best results, with a success rate of 87.7%, which was also associated with the location of graft placement (ventral vs. dorsal, P=0.025). Conclusion Dorsal onlay graft urethroplasty is better than ventral onlay. It is better to place the free skin graft in the dorsal part of urethra. Bulbar urethral stricture is more suitable for graft onlay urethroplasty than penile urethral stricture.