Objectives: Obesity and diabetes are the most common nutritional and endocrine disorders in developed and developing countries and are related to immune response alterations. Recent studies suggest an association among diabetes, obesity, and periodontitis. The aim of this study was to evaluate the relationship between neutrophil function alterations and periodontal disease severity of type 2 diabetic chronic periodontitis patients with and without obesity. Method and Materials: A total of 39 chronic periodontitis patients participated in the study. The study population was divided into 4 groups according to body mass index and type 2 diabetes status: (1) 8 type 2 diabetic obese patients, (2) 12 type 2 diabetic patients, (3) 8 obese patients, and (4) 11 systemically healthy patients as a control group. Neutrophil chemotaxis and phagocytosis functions and periodontal status were evaluated. Results: No differences in age, Gingival Index, Plaque Index, percentage of phagocytosis, phagocytic efficiency, and intracellular killing were observed among the groups, but chemotaxis was significantly lower in diabetic groups than the control group and probing depth was significantly higher in diabetic groups than the control group. Obesity did not seem to affect the results significantly for all parameters evaluated. Conclusions: Unlike in patients with type 2 diabetes, neither neutrophil functions nor periodontitis severity seemed to change in obese patients. However, in type 2 diabetic patients, neutrophil chemotaxis alterations seem to affect probing depth measurements.