Objective: The objective of the study was to compare the mean clinical attachment gain in patients of chronic periodontitis after scaling and root alone versus Azithromycin as an adjunct to scaling and root. Study Design Comparative study Place and Duration: Conducted at Operative Dentistry Department, Azra Naheed Dental College, Lahore for a duration of 4 months from December 2019 to March 2020. Methodology: Total Sixty patients fulfilling the selection criteria were randomly allocated to SRP and SRP+Az groups. In both groups, conventional scaling and root planing was done. In the SRP group placebo capsules were prescribed, while in the SRP+Az group, Azithromycin (500mg) once daily was prescribed for 3 days. Clinical attachment level (CAL) was measured initially and after 5 weeks. Data was analyzed in SPSS version 19.0 using independent sample t-test. Results: Both groups showed gain in CAL compared to baseline. However, SRP+Az group showed significantly more gain in CAL in comparison to SRP group (P value < 0.05). Conclusion: Use of Azithromycin adjunctive to SRP is an effective treatment modality in chronic periodontitis patients. Keywords: Anti‐Bacterial Agents, Azithromycin, Chronic periodontitis, Clinical attachment level, Periodontal Debridement, Scaling and root planing,