INTRODUCTION:Conventional periodontal therapy is an effective line of treatment for moderate periodontitis patients. Act of adjunctive use of other biomaterials assist in increasing the success of this therapy. One of these adjunctive treatments is the use of tea tree oil (TTO) as a locally delivered agent. OBJECTIVE: The present work aims to assess clinically the effect of intra pocket application of TTO gel in patients with moderate periodontitis. MATERIALS AND METHODS: this randomized controlled clinical trial was performed on a total number of thirty pockets in thirty patients with moderate periodontitis. They were classified into a control group which comprised fifteen patients treated with scaling and root planing SRP only and a test group which comprised fifteen patients treated with SRP and locally delivered TTO gel. The clinical parameters measured were: Probing pocket depth, clinical attachment level and bleeding upon probing. These were evaluated from baseline examination to three months follow-up. RESULTS:The clinical parameters showed improvement in the test group when compared to control group. CONCLUSION: The local delivery of TTO gel in conjunction with conventional periodontal treatment in moderate periodontitis is more effective than SRP therapy alone.