Objective To establish a chemiluminescence immunoassay(CLIA)for the detection of serum thyroid function.Methods The clinical data of 121 patients with hyperthyroidism,101 patients with hypothyroidism and 67 patients with normal thyroid function admitted to Tianjin Medical University General Hospital were retrospectively analyzed from February 2023 to May 2024.The levels of serum thyroid stimulating hormone(TSH),free thyroxine(FT4)and free triiodothyronine(FT3)were examined by CLIA,and then the linear range,precision and accuracy of TSH,FT4 and FT3 monitored by CLIA system were counted.Results The linear correlation coefficient(r)values of TSH,FT4 and FT3 were≥0.990,and slope(b)was within 0.95-1.00.The intra-batch and inter-batch precision values of TSH,FT4 and FT3 were less than 1/4TEa(CLIA'88)and 1/3TEa(CLIA'88)respectively.The bias of TSH,FT4 and FT3 were less than 1/2TEa(CLIA'88).The levels of TSH,FT4 and FT3 in patients with hyperthyroidism,hypothyroidism and normal thyroid function detected by CLIA were higher than those detected by RAI(P<0.05).Conclusion CLIA has good accuracy and precision in the detection of three items of serum thyroid function,and provides an important basis for clinical detection of three indexes of serum thyroid function.