In order to study the relationship between growth situation and thyroid-related hormones in Amur rat-snake (Elaphe schrenckii), Southern Amur rat-snake (E. anomala) and Keeled rat-snake (E. carinata) at captivity, we obtained the serum of these three species by drawing blood from the tail vein in the non-hibernation period of snakes in May, July and September, detected the thyrotropin-releasing hormone(TRH), thyroid-stimulating hormone (TSH), thyroid hormone (T4) levels and recorded their body weight, length and food intake. The data were analyzed by covariance analysis taking body weight as a covariate for multiple comparisons between groups with LSD method (ANCOVA) and Pearson correlation coefficient with SPSS STATISTICS, Version 17.0. Results were presented as mean ± standard deviation (SD) and statistical significance was declared at P < 0.05. The results showed that TRH, TSH and T4 peaks of all three species appeared in July (except for the thyroid hormone of E. anomala) (Table 2). Analysis of covariance revealed that TRH, TSH and T4 contents in three sampling time points were not significantly different in all three species (P > 0.05). Multiple comparisons between groups revealed that there existed difference in TRH, TSH and T4 contents at different sampling time points in three species (P < 0.05). Analysis of covariance revealed the difference in TRH, TSH and T4 contents of three species in the same sampling point was not significant (P > 0.05), but multiple comparisons between groups revealed that the TRH, TSH and T4 contents of E.carinata were significantly lower than those of E. schrenckii and E. anomala (except for the TRH in May) (P < 0.05); the difference between any two species of ratsnakes in TRH, TSH and T4 contents in Sep was significant (P < 0.05, Table 2). In addition, the correlation coefficient between E. schrenckii′s T4 content and food intake was 0.946, higher than in E. anomala and E. carinata (Table 3) and the feed conversion rate was 13.16% in E. schrenckii, higher than in E. anomala and E. carinata (Table 1). Summary: There is obvious difference in TRH, TSH and T4 contents in different snakes in the non-hibernation period, and there is a close correlation between T4 content, growth, food intake and feed conversion rate in snakes.