The high incidence of differentiated thyroid carcinoma (DTC) leads to a significant increase in the number of patients with lung metastatic DTC (LMDTC), making this population a key focus and challenge in clinical practice, so there is an urgent need to find effective methods to guide risk stratification and predict the risk of metastasis in this group of patients. This study is significant in its theoretical and technical advancement as it based on primary lesion 4D label-free proteomic analysis, combined with PRM validation, to identify potential biomarkers (8 key DEPs) for predicting DTC lung metastasis.