Update publication information. Here, we performed plasma extracellular vesicles (EVs) proteomics on 20 β-thalassemia major (TM) patients, 20 intermedia (TI) patients, and 20 healthy controls to explore the subgroup characteristics and the potential biomarkers. The proteome of paired plasma was analyzed in parallel to compare the biomarker potential of both specimens. We first described the pathophysiological characteristics of different subtypes. More significant immunity abnormalities and lipid metabolism was separately observed in patients with TI and TM, which was consistent with the results of paired plasma proteomics. A diagnostic model consisting of six proteins with subtyping potential was proposed. Of note, superior performance of plasma EVs on patient subgroup differentiating was shown than plasma, demonstrating the potential of secreted EVs for diagnosis of β-thalassemia patients.