Background Periodontal disease is a chronic inflammatory disease initiated by bacterial pathogens and modified by various risk factors. Various studies have elucidated the converse side of the relationship between systemic health and oral health proving the adverse effect of systemic health on periodontal disease and vice-versa. Amongst all, a strong correlation has been shown between periodontal disease and diabetes, revealing that periodontitis is a proven sixth complication for diabetes. There is emerging evidence to support the existence of a two-way relationship between diabetes and periodontitis, with diabetes increases the risk for periodontitis and its inflammation affecting the glycemic control. Method The aim of this case-control study was to evaluate the periodontal and hematological manifestations in diabetic and non-diabetic patients. The sample size was estimated as n=264 with n=132 in each group. 2.5 ml of blood was withdrawn from each of the patient for hematological evaluation: HbA1c values, Hb%, RBC count, the differential count, and total leukocyte count. Periodontal evaluations were assessed by probing pocket depth, clinical attachment level, and Russell's periodontal score. Results There was statistically significant (p=0.000) difference in the diabetic group than the control group with respect to smoking, alcohol consumption, Hb%, HbA1c levels, differential counts, total leukocyte count, probing pocket depth, clinical attachment level, and Russell's periodontal score. RBC count and gender revealed no significance. Conclusion There were a higher periodontal manifestation corresponding to the altered hematological findings in diabetic patients than non-diabetic patients with higher prevalence in smokers and alcohol consumers.