Psoriasis is a major common and relapsing skin disease, which is often both physically and psychologically disabling.Photochemotherapy (PUVA) is still a viable option for treatment of psoriasis. However, the major concerns about its carcinogenic potential have raised the urgent need to change current PUVA protocols.In this study, a prospective comparative trial between two groups of patients with chronic plaque psoriasis was carried out to determine whether reducing the treatment frequency of PUVA to twice/week instead of three times/week would affect the therapeutic response of PUVA therapy.Results of the study revealed no statistically significant difference in PASI final and in the percentage of reduction of PASI score between both groups (P value > 0.05), while there was a significant difference in the total number of sessions and the total cumulative UVA doses between both groups (P value < 0.001).Our study suggests that reducing the treatment frequency of PUVA and consequently the cumulative UVA dose does not compromise the efficacy of PUVA, but it may even improve the benefit/risk ratio of PUVA therapy.