Objective: Analysis of the metabolic differences among the papillary thyroid carcinoma (group T) patients, benign thyroid tumor patients (group B) and healthy controls (group H) by nuclear magnetic resonance hydrogen spectrum. Methods: collect twenty serum specimens each from group T, group B and group H. Collect image archive. Use Topspin software, AMIX software and SIMCA-P+ software to calibrate, integrate with PCA and PLS-DA, research the three groups’ serum for endogenous metabolic differences. Results: The data of group T and group H established a discrimination model, and the model is correct (P