Fatma A. Ata¹, Samah H. El-Meadawy^2,Mohamed M. Anees³, Hamdy F. Marzouk^{4 1}. Teaching Assisstant of Oral Medicine and Periodontology, Faculty of Dentistry, Mansoura University, Mansoura, Egypt. ²Associate professor of Oral Medicine and Periodontology, Faculty of Dentistry, Mansoura University, Mansoura, Egypt. ³Assistant professor of Oral Medicine and Periodontology, Faculty of Medicine, Mansoura University, Mansoura, Egypt. ⁴ Professor of Clinical Pathology , Faculty of Dentistry, Mansoura University, Mansoura, Egypt. Abstract: Objectives:to assess the effect of conventional periodontal treatment (scaling and/or root planing) on the levels of salivary AST, ALT, GGT, ALP, ACP enzymes in chronic gingivitis and chronic periodontitis patients. Subjectsand Methods:This study included 20 patients with chronic gingivitis, 23 patients with chronic periodontitis, and 20 controls. Salivary AST, ALT, GGT, ALP, ACP enzymes levels were determined spectrophotometrically using commercially available kits at baseline and 4 weeks after treatment. All clinical parameters also evaluated at each time interval. Results:The activities of AST, ALT, GGT, ALP and ACP enzymes were significantly increased in the saliva of patients with chronic gingivitis and chronic periodontitis in relation to those healthy. After periodontal treatment the activities of examined salivary enzymes were significantly decreased. Conclusion: salivary (AST, ALT, GGT, ALP and ACP) enzymes can be considered as the biochemical markers of the functional condition of periodontal tissues which provides new opportunities in making diagnoses and following the efficiency of curing periodontal disease. Keywords: Diagnosis, Periodontitis, Saliva, Enzymes.