Aims: Hepatozoonosis, caused by a protozoan parasite Hepatozoon canis, is important for canine health due to its ability to cause chronic, debilitating disease, and the challenges it presents in terms of diagnosis and management. The present study was conducted to see the effect of H. canis infection on various haematological and biochemical parameters as compared to the normal healthy dogs in order to understand the disease pattern and suspecting the disease. Study Design: The clinically affected dogs that come to the veterinary hospital with symptoms of hepatozoonosis were included in the study. Haematological and biochemical parameters of dogs found positive for hepatozoonosis were analysed. The values of these parameters were subsequently compared to healthy animals in order to identify any significant difference caused by H. canis. Place and Duration of Study: The studied was conducted at Department of Veterinary Medicine, DUVASU Mathura, India. Total 212 blood samples were collected from the dogs that were brought for the treatment in between February 2023 to March 2024. Methodology: Total 212 dogs were included in the present study out of this 46 dogs were found positive with H. canis using PCR based molecular test. These positive animals were subjected to study the changes in biochemical parameters like blood urea nitrogen, creatinine, alkaline phosphatase, alanine transaminase, aspartate amino transferase, total leucocyte count, total erythrocyte count, haemoglobin, haematocrit, erythrocyte indices (MCV, MCH, MCHC), differential leucocyte count, platelet count and platelet indices (MPV, PDW) using autoanalyzer. Student's t-test in Graphpad Prism was used to compare these values to healthy animals. Results: The study confirms that Hepatozoonosis leads to significant haematological and biochemical changes in dogs. Infected dogs have lower Hb, TEC, and PCV than healthy animals, indicating anaemia. Thrombocytopenia and leukocytosis were also observed in the infected animals. Non-significant differences in MCV, MCH, and MCHC indicate normocytic, normochromic anaemia. Anisocytosis and non-regenerative anaemia is indicated by significant RDW-CV increases with decrease in MCV values. Increased liver-specific enzymes like ALT, AST, and ALP and kidney-related enzymes like BUN and CRT suggest hepatic and renal involvement in disease pathophysiology. Conclusion: In hepatozoonosis, haemato- biochemical parameters like non-regenerative anaemia. anisocytosis, thrombocytopenia, leukocytosis, low serum protein concentration and increased ALT, AST, ALP and BUN values may be used as non-specific biomarkers. The results can be used in making clinical decisions and monitoring therapeutic responses in cases of hepatozoonosis.