INTRODUCTION: Beta glucuronidase (βG) is one of the enzymes involved in the destruction of non– collagenous components of extra cellular matrix that contributes significantly to tissue destruction and the pathogenesis of periodontal disease. OBJECTIVE : Aim of the study was to estimate the effect of non–surgical periodontal therapy (NSPT) on salivary βG in chronic periodontitis (CP) with and without smokeless tobacco (ST) and to evaluate the relationship between beta glucuronidase activity and periodontal clinical parameters. METHODOLOGY: The study consisted of 100 subjects (25 each) – healthy, gingivitis, CP with and without ST. Clinical parameters and salivary βG were measured at baseline and 4 weeks after non– surgical periodontal therapy using spectrophotometer at 550 nm. Statistical analysis was carried out using paired t test, chi–square , analysis of variance (ANOVA). RESULTS: The mean βG values in saliva were found to be significantly higher in periodontitis with smokeless tobacco subjects after 1 month NSPT, compared at baseline. (p<0.001) CONCLUSION: Successful NSPT lead to progress in inflammatory condition, regulating βG levels & effect of ST on periodontium. Thus, can be used as potent biomarker for periodontal disease activity.