Obesity has been associated with a number of health issues and is a major global public health concern. The purpose of this study was to look at the relationship between an adult's body mass index (BMI) and their hematopoietic profile. Material and methods: 500 participants (aged 20 to 60) who attended the outpatient division of a tertiary care hospital in the India participated in a cross-sectional study. Standard laboratory procedures were used to measure the haematological parameters Hb, red blood cell count, “white blood cell (WBC)” count, platelet count, and mean corpuscular volume. Using information on height and weight, BMI was computed. The relationship between the haematological profile and BMI was discovered using multiple linear regression analysis. Results: After correcting for age, sex, smoking status, and physical activity, the results showed that BMI was positively linked with haemoglobin (β = 0.23, P 0.001), red blood cell count (β = 0.18, P 0.001), WBC count (β = 0.13, P = 0.003), and platelet count (β = 0.14, P = 0.002). Mean corpuscular volume and BMI did not, however, significantly correlate (β = -0.03, P = 0.51). Conclusion: These findings imply that changes in haematological parameters may be related to obesity, and physicians should think about monitoring these parameters in obese people to look for potential health consequences early on.