Acute　kidney　injury　(AKI)　is　associated　with　adverse　hospitalization.　Previous　studies　have　reported　that　an　elevated　triglyceride　glucose　(TyG)　index　is　significantly　associated　with　the　development　of　AKI　in　patients　with　cardiovascular　disease,　as　well　as　in　those　undergoing　surgery;　however,　the　potential　of　the　TyG　index　to　predict　AKI　following　neurotrauma　remains　unclear.　Patients　diagnosed　with　traumatic　brain　injury　(TBI)　in　Chinese　tertiary　hospitals　between　January　2014　and　December　2023　were　included　in　this　retrospective　study.　The　outcome　was　the　incidence　of　AKI.　TyG　was　identified　as　an　independent　risk　factor　for　AKI　using　logistic　regression　and　propensity　score　matching　(PSM).　Finally,　the　association　between　TyG　index　and　AKI　was　further　assessed　using　multivariate　logistic　regression,　restricted　cubic　spline　(RCS)　regression,　and　subgroup　analysis.　The　present　study　enrolled　1,505　patients　with　TBI,　of　whom　66.45%　were　male,　with　an　average　age　of　55.47　+/-　17.32　years.　The　incidence　of　AKI　was　9.4%.　Multiple　logistic　regression　analyses　identified　a　relationship　between　the　TyG　levels　and　AKI　risk.　This　relationship　was　retained　after　PSM.　A　significant　positive　correlation　between　TyG　level　and　AKI　was　observed　in　all　three　models　constructed　using　multivariate　logistic　regression.　RCS　regression　analyses　further　indicated　a　linear　increase　in　AKI　risk　with　an　increasing　TyG　index.　In　subgroup　analyses,　this　correlation　remained　stable　for　the　majority　of　the　population　but　could　be　influenced　by　sex.　TyG　levels　were　positively　correlated　with　the　risk　of　AKI　development　in　patients　following　TBI.　As　a　predictive　biomarker,　the　TyG　index　enables　effective　risk　stratification　and　customization　of　management　protocols　to　mitigate　AKI　in　these　patients,　thus　enhancing　clinical　outcomes.