Objective To discuss the clinical efficacy of 5% tea tree oil ointment in treating scaly blepharitis, which is associated with demodex. Methods In this prospective clinical study, a total of 240 outpatients diagnosed with scaly blepharitis in the Second Affiliated Hospital of Fujian Medical University between June 2007 and June 2013 were included in the study. The mean age was 48.7±13.7 years. Demodex was positive in every eyelash sample. The degree of ocular discomfort was judged by an ocular discomfort score. The method of treatment: Lid scrub with 5% tea tree oil ointment bilaterally once every night. Patients returned for evaluations every two weeks, and the success of the treatment was evaluated at the end of four weeks. Total follow-up time was 3 months. The final assessment included an evaluation of changes in the ocular discomfort score, demodex count, eyelid hygiene conditions and side effects. A paired t-test was used for comparison of data before and after the treatment. Results One hundred eighty of 240 patients (75.0%) had complete relief of symptoms after treatment, and 38(15.8%) had significant improvement. The mean ocular discomfort score was 8.2±3.2 before treatment, which dropped to 0.3±0.8 after treatment（t=12.28, P<0.01）. The eyelids of 212 patients (88.3%) became free of dandruff. The demodex count was 6.2±4.8 for every four eyelashes before treatment and declined to 0.7±0.6 for every four eyelashes after treatment （t=6.96, P<0.01）. None of the patients experienced an allergic reaction or had adverse reactions during or after the treatment. Conclusion Lid scrub with 5% tea tree oil ointment can effectively relieve the symptoms of scaly blepharitis, which is associated with demodex infestation and greatly diminishes the number of demodex mites. This shows that the treatment is safe and effective.