Objective To investigate the clinical effect of Liangxue Jiedu Decoction combined with narrowband ultraviolet B (NBUVB) in the treatment of pityriasis rosea. Methods A total of 82 patients with pityriasis rosea were randomly divided into treatment group with 43 patients and control group with 39 patients. The patients in the treatment group were given oral administration of selfmade Liangxue Jiedu Decoction combined with NBUVB, and those in the control group were given Liangxue Jiedu Decoction alone. Pityriasis Rosea Severity Score (PRSS), time to relief of itching, suspension of rash, and disappearance of rash, and clinical outcome were observed after 1 month of treatment. Results Both groups had a significant reduction in PRSS after treatment (P<0.05), and there was no significant difference in the reduction in PRSS between the two groups (P>0.05). There were significant differences between the two groups in the time to relief of itching, suspension of rash, and disappearance of rash (P<0.05). The treatment group had a significantly better clinical outcome than the control group (P<0.05). 〖JP〗Conclusion Oral administration of Liangxue Jiedu Decoction combined with NBUVB irradiation has a better clinical effect than oral administration alone in the treatment of pityriasis rosea, with few adverse effects.