This study explores the association between mean platelet volume (MPV) and other hematological parameters in children with diabetic ketoacidosis (DKA), aiming to identify hematological changes and their implications for management and treatment strategies in pediatric type 1 diabetes mellitus (T1DM). In a retrospective, two-center analysis of 323 children, participants were categorized into three groups: DKA, T1DM without ketoacidosis, and healthy controls (95). Hematological parameters and HbA1c levels were collected. Blood pH levels classified DKA severity, and statistical analyses included One-way ANOVA, correlation tests, receiver operating characteristic curve analysis, and logistic regression to assess the predictive value of hematological parameters for DKA. No significant demographic differences were noted among the groups. Patients with DKA exhibited significantly lower MPV and higher neutrophil-to-lymphocyte ratio (NLR) compared with both patients with T1DM without ketoacidosis and healthy controls. Logistic regression showed MPV ≤9.35 and NLR ≥2.73 significantly increased DKA risk. This study demonstrated a significant relationship between DKA and altered hematological parameters (MPV and NLR) in pediatric patients, highlighting their potential as markers for early detection and risk assessment of DKA.