Diiodothyronine (formula C₁₅NO₄H₁₃I₂), triiodothyronine (formula C₁₅NO₄H₁₂I₃), and tetraiodothyronine (formula C₁₅NO₄H₁₁I₄) are the major hormones secreted by the thyroid gland, which contribute to the development of the human brain, the synthesis of neurotransmitters, the regulation of metabolism and the normal functioning of thyroid function playing a crucial role. Three compounds of C₁₅NO₄H_nI_m(n=11, 12, 13, m=4, 3, 2, n+m=15) have been studied systematically by theoretical calculations in this paper, which provides a detailed theoretical basis for future experimental research. In this research, combining the Gaussian software package and GaussView software to carry out theoretical calculation, the geometrical and electronic structures of C₁₅NO₄H_nI_m(n=11, 12, 13, m=4, 3, 2, n+m=15) clusters are optimized by using density functional theory (DFT) at the B3LYP/Lanl2mb level. Then, based on these clusters’ stable ground state structure, the excited state absorption and emission spectra are studied at the same basis set level using the polarized continuum model (PCM) with time-dependent density functional theory (TDDFT). The results show that the geometrical structure symmetry of the optimized C₁₅NO₄H_nI_m (n=11, 12, 13, m=4, 3, 2, n+m=15) clustersare C₁; based on the stable structure of the ground state for C₁₅NO₄H_nI_m (n=11, 12, 13, m=4, 3, 2, n+m=15) clusters, the transport properties are obtained, C₁₅NO₄H₁₃I₂ has neither p-type transport property nor n-type transport property, the C₁₅NO₄H₁₂I₃ and C₁₅NO₄H₁₁I₄ clustersare p-type transport material; and then, based on the theory of time-dependent density functional, the solvent effect is calculated based on the optimized ground state structures. Meanwhile, the absorption spectra characteristics of the molecules in water solventare further obtained, and the chiral spectra of the C₁₅NO₄H_nI_m(n=11, 12, 13, m=4, 3, 2, n+m=15) clusters are also studied by ECD. The theoretical research can provide a comparable theoretical value for the experimental research and a feasible reference value for future experimental research.