Thyroid 4b puncture did not find cancer cells is usually a good thing, mostly represents benign nodules, but still need to be closely followed up and observed, there is a possibility of false negative puncture. According to the guideline of “2020 Chinese Guidelines for Ultrasound Malignancy Risk Stratification of Thyroid Nodules: C-TIRADS”, the likelihood of malignancy for TIRADS grade 4b thyroid nodules is about 10% to 50%, and ultrasound-guided puncture biopsy of the nodule is recommended. Puncture biopsy is primarily used to more accurately assess the benignity or malignancy of a nodule, and if the puncture pathology results do not reveal cancer cells, a cancerous nodule can be tentatively ruled out, which means it is represented as a good thing. For TIRADS grade 4b thyroid nodules, even if the puncture does not reveal cancer cells, regular follow-up is still recommended.