Objective: To investigate the relationship between complications of massive cerebral infarction (MCI) and composite in ammatory ratios. Study Design: A case-control study. Place and Duration of the Stud:y Department of Neurology, A liated Hospital of Putian University, Putian, China, from January 2019 to November 2021. Methodology: Eighty-two patients with MCI underwent blood tests within 24 hours of admission. Complications such as cerebral herniation, haemorrhage transformation (HT), and stroke-associated pneumonia (SAP) were evaluated based on imaging examinations. The prognosis was assessed using the modi ed Rankin Scale score (mRS) at discharge. Results: Among the 82 patients, the cerebral herniation group had higher levels of systemic immune in ammation index (SII) and neutrophil-to-lymphocyte ratio (NLR) compared to the non-cerebral herniation group. MCI patients who developed HT had higher levels of SII, NLR, mean platelet volume/platelet (MPV/PLT), and platelet-to-lymphocyte ratio (PLR). The SAP group had higher levels of MPV/PLT and NLR compared to the non-SAP group. The poor prognosis group had higher SII and NLR levels but a lower lymphocyte-to-monocyte ratio (LMR) compared to the good prognosis group. Conclusion: NLR showed high accuracy in predicting complications and the short-term prognosis of MCI. SII was linked to cerebral herniation, HT, and the short-term prognosis of MCI. MPV/PLT was found to be related to SAP and HT caused by MCI. LMR may act as a protective factor for the short-term prognosis of MCI.