Aim of the study: To evaluate and compare the effect of Conventional aPDT (Photosensitizer and laser) with PDTPLUS (Sub-Gingival Oxidative Irrigant, photosensitizer and laser) in treatment of chronic periodontitis patients. Methodology: An in-vivo study in which microbiological evaluation was done by allocating two groups having 15 subjects in each group with presence of chronic periodontitis. Group A consists of 15 patients which includes the treatment of Scaling and root planning (SRP) along with Conventional aPDT therapy while Group B consists of other 15 patients include treatment SRP with PDTPLUS therapy. A detailed case history and complete periodontal examination was done including a) Pocket probing depth; b) CAL; c) Plaque index; d) Bleeding on probing; e) Periodontal index. Therefore, GCF samples were collected for microbiological evaluation which includes CFU of gram-ve anaerobic bacteria. Thorough scaling and root planning was done in both the groups followed by Photodynamic Therapies. Follow-up of clinical as well as microbiological evaluation was done at 30th and 90th day. Result: Reduction in periodontopathic bacteria, probing depth and CAL, were clinically significant in chronic periodontitis patients when treated by PDTplus . Conclusion: The study can be concluded that PDTplus can be a beneficial treatment protocol being less traumatic, non-invasive, quicker, site specific and less time-consuming therapy in comparison to periodontal surgeries.