Objective To analyze the genotypic and phenotypic characteristics of four thrombotic patients carrying heterozygous mutations in the disintegrin-like domain of ADAMTS13 (a disintegrin and metalloproteinase with thrombospondin type 1 motifs 13), and to explore the association between ADAMTS13 deficiency and thrombosis. Methods Thrombophilia-related gene mutations were screened in thrombosis patients using a thrombophilia gene panel, identifying four thrombophilia pedigrees carrying mutations in the ADAMTS13 disintegrin-like domain. Coagulation function was assessed using clotting tests. Antigen and activity of von Willebrand factor (vWF) were measured using immunoturbidime-try, and its collagen-binding capacity was measured using enzyme-linked immunosorbent assay (ELISA). The distribution of vWF multimers was analyzed by SDS-agarose gel electrophoresis with gray value semi-quantitative analysis. ADAMTS13 activity in plasma was measured by fluorescence resonance energy transfer assay, and its antigen levels were quantified via ELISA. Comparative analysis of three-dimensional structures between wild-type and mutant ADAMTS13 proteins was performed using PyMOL software. Results The probands from four pedigrees experienced thrombotic events of varying seve-rity, including cerebral venous sinus thrombosis, pulmonary embolism, and lower extremity deep vein thrombosis. Mutations in the ADAMTS13 disintegrin-like domain accounted for approximately 4/87 of ADAMTS13 heterozygous mutations. Genetic analysis showed that all four probands carried heterozygous mutations in the ADAMTS13 disintegrin-like domain (p.Pro301Ala, p.Pro301Arg, p.Arg349Cys), with p.Pro301Ala and p.Pro301Arg being newly reported. Coagulation tests demonstrated significantly reduced ADAMTS13 activity and antigen levels (Act: 57.42%-72.88%, Ag: 66.94%-78.34%), and elevated vWF activity and antigen levels (Act: 158.2%-213.7%, Ag: 167.2%-216.6%). Electrophoretic analysis of vWF multimers showed a significantly increased proportion of high-molecular-weight multimers (HMWMs) in patient plasma (Gray value: 166.6-218.9 vs 117.4), indicating markedly elevated HMWMs compared to normal controls. Structural analysis further suggested that the mutation sites were located in critical regions of the ADAMTS13 disintegrin-like domain, potentially disrupting protein stability and its binding capacity with vWF. Conclusion This study first reports two novel missense mutations—Pro301Ala and Pro301Arg—located in the disintegrin-like domain of the ADAMTS13 protein, and further verifies the pathogenic characteristics of the known Arg349Cys mutation. The results demonstrate that these mutations result in reduced ADAMTS13 protein expression levels and significantly decreased enzymatic activity, as evidenced by impaired cleavage capacity of high-molecular-weight vWF multimers. Functional tests confirm abnormally increased vWF multimers in patients, disrupting the dynamic balance of the ADAMTS13-vWF axis and consequently increasing thrombotic risk.