Background: Diabetes mellitus and smoking are considered as two major risk factors that influence the severity and progression of periodontal disease. Severity and prevalence of periodontitis varies in different countries of the world and there are indications that may be extensive in developing more than high developed countries. Objective: The present study was designed to evaluate the periodontal conditions and severity of chronic periodontitis patients in relation to smoking and diabetes at Holy Makkah city. Materials and Methods: Two hundred and fifty-four patient adult male chronic periodontitis patients were participated in this study, their age ranging from 24 to 60 years old with mean age of 37.50 ± 0.13 years. The patients were selected from enrolled individuals at screening unit in three dental centers at Makkah city. The selection of chronic periodontitis patients were based on two major risk factors in presence or absence of smoking and diabetes mellitus and they categorized into the following four groups G1: Non diabetic nonsmokers, G2: Diabetic nonsmokers, G3: Non diabetic smokers, G4: Diabetic smokers. The periodontal status was evaluated by four clinical parameters: Plaque Index (PI), Bleeding Index (BI), Probing Pocket Depth (PD) and Clinical Attachment Loss (CAL). Results: The results were revealed the comparisons between the mean values of clinical parameters; PI was highly significant in G2 compared to G1 and G3. BI was significant in G2 versus to G1, and highly significant in G4 contrast to G1and G3. PD was significantly increased in G2 than G1, and highly significant in G4 related to G1, G2 and G3. CAL was significant in G4 compared to G3, highly significantly increased in G4 than G1 and G2, whereas, high significant in G4 contrast to G3. Severity forms of periodontitis in each group categorized into; mild, moderate and severe;