Abstract: Objective To find out the differences of the curative effect for psoriasis between percentage dose schemes and fixed dose schemes in narrowband ultraviolet B(NB UVB)phototherapy. Methods From October 2014 to March 2015, according to the principle of randomization, control and blindness, 63 patients admitted to Chinese PLA General Hospital were divided into test group(n= 33)with 23 males and 10 females undergoing percentage dose schemes and control group(n=30)with 23 males and 7 females undergoing fixed dose schemes group in the process of narrowband ultraviolet B(NB-UVB)phototherapy.There was no statistical difference between two groups in age, gender and pre-treatment psoriasis area and severity index(PASI)score. Results After three weeks of treatment, the PASI score of test group(5.00±1.275)and control group(5.47±1.479)had no statistically significant difference in curative effect.After five weeks of treatment, compared with control group, the PASI score of test group was higher (1.73±1.626)vs(2.67±1.322), and the curative effect was better than control group. Conclusion In the two dose-increasing schemes of narrowband ultraviolet B(NB UVB)phototherapy for the treatment of psoriasis, percentage dose scheme is the prime choice in terms of efficacy.