Background: The excimer laser is a new therapeutic option in the treatment of psoriasis vulgaris. Objective: The purpose of this study was to determine the response of psoriasis lesions to the 308-nm excimer laser compared to 311-nm UVB phototherapy. Methods: In this prospective right/left comparative, open, single-blinded trial, selected psoriasis plaques of 16 patients were treated with the excimer laser whereas the rest of the body was treated with UVB narrow-band phototherapy. A modified PASI score was used to evaluate the results. Results: After 12 treatments, 15 patients were evaluated. In 2 patients no difference between the two body sides was observed. In 9 patients the laser-treated lesions showed better results, whereas in 4 patients the side treated with 311-nm UVB showed more clearing. The mean reduction in PASI score was 5.6 and 4.9, respectively (difference not significant). Conclusion: The use of the 308-nm xenon chloride excimer laser is an additional effective therapeutic option for the treatment of psoriasis vulgaris.