BACKGROUND: Traumatic brain injury (TBI) contributes greatly to high rates of death and disability globally. It may be divided into primary and secondary injuries. Primary head injuries occur at the moment of impact which causes mechanical loads and accelerations both linearly and rotationally, causing injury to the brain. After the primary brain injury, further biochemical and cellular processes occur that lead to secondary injury. Secondary insult in TBI may lead to several neuroinflammation processes that are reflected on laboratory markers. The monocyte-lymphocyte ratio and mean platelet volume-platelet count ratio (MPVPCR) theoretically have the potential to be used as neuroinflammation markers in TBI. AIM: This study was conducted to assess the relationship between monocyte-lymphocyte ratio (MLR), MPVPCR with both C-reactive protein (CRP), and erythrocyte sedimentation rate (ESR) regarded as inflammation markers in relation to secondary brain injury. METHODS: This study was a cross-sectional prospective analytic observational study conducted at the Sanglah hospital emergency department from February to May 2022. Patients diagnosed with TBI aged 18 years and over that were willing to be included in the study by consecutive sampling. Patients with a history of autoimmune disease, history of taking immunosuppressant drugs, and fractures of > 2 long bones were excluded and the presence of infection characterized by fever was excluded from the study. History taking and physical examination were done to obtain data regarding age, gender, mechanism of injury, Glasgow Coma Scale, fainting duration, and memory loss. The blood sample was taken at 24 h after trauma to obtain MLR, MPVPCR, CRP, and ESR results. Pearson correlation test was done to determine the correlation between MLR and MPVPCR with CRP and LED. RESULTS: There are a total of 85 patients included in this study with the mean of age which is 36 ± 2.5 years old. Most of them are men (71.3%) with the mean of GCS on admission which is 12. Mean ± (SD) of the monocyte, lymphocyte, and platelet was 1.12 ± 0.82 × 103/μL, 1.83 ± 1.69 × 103/μL, and 259.34 ± 85.79 × 103/μL consecutively. MLR with CRP had a weak positive correlation and was statistically significant (r = 0.215; p = 0.045), as well as MPVPCR with ESR also had a weak positive correlation and was statistically significant (r = 0.276; p = 0.010). While both MLR with ESR and MPVPCR with CRP had no correlation. CONCLUSION: MLR can be an option representing CRP in predicting the magnitude of inflammation in head injury and MPVPCR can be considered to be used as a predictor of thrombotic phenomena in TBI.