The invention discloses a preparation method of 
saliva extracellular vesicles and application of the 
saliva extracellular vesicles to molecular diagnosis.The preparation method includes the steps of removing high-abundance proteins from 
saliva samples, filtering out 
mucoproteins, separating and extracting the 
extracellular vesicles, characterizing the obtained 
extracellular vesicles, extracting 
extracellular vesicle proteins, identifying the 
extracellular vesicle proteins and applying the 
extracellular vesicle proteins to 
lung cancer biomarker discovery.Currently, a normalized saliva extracellular 
vesicle preparation technology is absent, and high-abundance 
protein interference and background 
impurity interference, existing in existing preparation technologies, result in shortcomings of low extracellular 
vesicle recovery rate, fewer identified proteins and the like, so that true extracellular 
vesicle proteomics information can be reflected difficultly.The preparation method of the saliva 
extracellular vesicles and application of the saliva 
extracellular vesicles to molecular diagnosis have the advantages that saliva of healthy adult volunteers and 
lung cancer patients is taken as the samples, and an 
affinity chromatography and membrane separation combined technology is adopted, so that after the high-abundance proteins and the 
mucoproteins of the saliva are removed, the extracellular vesicles in the saliva are extracted centrifugally, proteomes of the extracellular vesicles are analyzed and more extracellular vesicle proteins are identified.