Objective: This study aimed to assess the usefulness of narrow band UVB (NB-UVB) therapy in Yemeni patients with different skin conditions. Methods: A prospective clinical audit was conducted of 120 Yemeni patients (45 males and 75 females), aged 5-54 years from all patients with different skin diseases in dermatology clinic (January 2013 -May 2014), treated by NB-UVB irradiation without being combined with topical steroid or topical chemotherapy during the course of the study. Results: 120 patients enrolled in this study with mean age 25.8 +/- 12.6 years old. Females consisted of the major rate (62.5%), and patients who came from Aden had a high rate (77.5%). Ninety four (78.3%) patients had complete response to treatment, 6.7% had partial and 15% had no response. Mycosis fungoid and atopic dermatitis had a high mean number of session (84.50 +/- 0.70), followed by vitiligo with mean number of sessions 27.10 +/- 23.70. The Lichen planus, Mycosis and Pityriasis had complete response (100%) to treatment, followed by vitiligo 79.3%, while partial response appeared in patients with alopecia (66.7%) and atopic dermatitis (22.2%). Patients with chronic renal failure had no response to treatment in 33.3%, followed by Parapsoriasis (20%). Conclusion: Our study proves that NB-UVB therapy is an effective and safe tool in the management of skin diseases and is considered the first-line phototherapeutic option for many skin conditions.