Objective:To explore the expression of serum inflammatory factors in patients with thyroid tumor and their correlation with thyroid hormones.Methods:A total of 92 patients with thyroid tumors (48 cases of thyroid cancer and 44 cases of thyroid adenoma) admitted to Department of Endocrinology in Linyi Central Hospital in Shandong Province from Jan. 2020 to Oct. 2021 were enrolled. 50 healthy volunteers who received physical examination in the hospital during the same period were enrolled in the control group. The serum inflammatory factors [tumor necrosis factor-α (TNF-α) , interleukin-6 (IL-6) , interleukin-17 (IL-17) ] and thyroid hormone expression levels [thyroid stimulating hormone (TSH) , free thyroxin T4 (FT4) , free triiodothyronine (FT3) ] of the three groups were detected. Analysis of variance was used for multi-group comparison, independent sample t test was performed for comparison between groups, Spearman correlation analysis and Logistic regression analysis were made for the risk factors of thyroid cancer. The expression of serum inflammation and thyroid hormones in patients with different stages of thyroid cancer was observed. Results:Serum TNF-α, IL-17, IL-6 from high to low were in the thyroid cancer group (74.61±7.94 ng/L, 68.65±7.05 ng/L, 20.52±2.84 ng/L) , thyroid adenoma group (26.97±3.42 ng/L, 46.31±5.31 ng/L, 13.61±1.58 ng/L) , control group (18.82±2.63 ng/L, 34.52±4.02 ng/L, 8.97±1.06 ng/L) ( F=1596.271, 468.602, 423.351, all P<0.001) ; Serum TSH levels from high to low were in the thyroid cancer group (8.64±1.34 mU/L) , the thyroid adenoma group (5.21±1.02 mU/L) , the control group (3.94±0.85 mU/L) ( F=242.182, P=0.000) . There was no significant difference in serum FT4 or FT3 levels among the three groups ( P=0.753, 0.634) . Correlation analysis indicated that serum TNF-α, IL-17, and IL-6 were positively correlated with the expression level of serum TSH ( r=0.936, 0.726, 759, all P<0.05) . The expression level of TNF- α, IL-17, IL-6 and TSH was significantly higher in patients of stage III and IV than that in patients of stage I and II ( t=2.541, 4.394, 6.390, 4.962, P=0.015, P<0.001, P<0.001, P<0.001) . Multivariate Logistic regression analysis suggested serum TNF-α, IL-17, IL-6 and TSH were all risk factors for thyroid cancer. Conclusions:Serum inflammatory factors and some thyroid hormones (TSH) are generally highly expressed in patients with thyroid tumors, the expression levels of serum inflammatory factors are correlated with the expression of TSH. There are statistically significant differences in the expression levels of serum inflammatory factors and TSH between patients with thyroid cancer of different stages, serum inflammatory factors and TSH are also involved in the occurrence and development of thyroid cancer, and are risk factors for thyroid cancer.