Thyroid tumors have become the fastest rising solid tumor malignancy in recent years. The detection rate of thyroid nodules by palpation in the general population is 3-7%, while the detection rate by high resolution ultrasound can be as high as 20-76%. This means that about half of the population may have a nodule in the thyroid gland, and 5-15% of these may be malignant. How to identify benign and malignant thyroid nodules easily and quickly, so as to achieve early detection and early treatment has become an urgent problem in thyroid tumor today. Although the development of tumors is thought to have a genetic basis, recent studies have found that the host immune response also plays an important role in the development of malignant tumors. Several indicators of systemic inflammation reflected in hematology have been shown to be associated with the prognosis of several malignancies, in particular the neutrophil-to-lymphocyte ratio (NLR)). Although NLR is inferior to other indices reflecting inflammatory conditions, it has unique advantages due to its low cost and its use as a routine test. It is clear that if the prognostic value and clinical efficacy of NLR is proven, it will become an important factor in identifying malignant tumor stratification. A study of thyroid cancer cases over many years revealed for the first time that NLR levels were higher in patients with thyroid cancer than nodular goiter in those aged ≥ 45 years, and that the increase in NLR levels was due to a decrease in lymphocyte count; in those aged < 45 years, there was no such difference; in those aged < 45 years, NLR levels in nodular goiter and thyroid cancer were positively correlated with age, and negatively correlated with Lymphocyte counts were negatively correlated; among patients with papillary thyroid cancer, those aged < 45 years had lower NLR levels than those aged ≥ 45 years, while lymphocyte counts were higher than those aged ≥ 45 years; NLR levels were higher in clinical stage III / IV papillary thyroid cancer than in stage I / II; the difference between the two may also be due to age.