Abstract: To study the characteristics of mtf-1 gene of Siniperca chuatsi and the effects of cadmium stress on the circadian rhythm of mtf-1 gene in brain, we analyzed cis-regulatory elements of mtf-1 gene promoter, sequence characteristics and tissues expression patterns of mtf-1 gene, and explored the circadian rhythm changes of mtf-1 gene expression in brain of Siniperca chuatsi under cadmium stress. The results showed that there were binding sites of zinc finger proteins including ZNF136, ZNF384 and ZNF143 in the mtf-1 promoter of S. chuatsi, indicating that their expression is potentially regulated by metal ions. In addition, RORβ binding sites of the core clock gene were also found in the mtf-1 promoter of S. chuatsi, indicating that the mtf-1 gene is potentially involved in circadian rhythm regulation. The analysis of function domain indicated that mtf-1 gene has a highly conserved DNA binding domain and a non-conserved trans-activation domain. mtf-1 gene is expressed in different tissues of S. chuatsi, among which the highest expression level is found in brain tissue, followed by kidney. Under natural conditions, mtf-1 gene showed a trend of high expression at night and low expression in the brain at day. The expression peak phase occurs at ZT 12.65h (nightfall), which is consistent with its life habits. Under cadmium stress, the mtf-1 gene in the brain of S. chuatsi presented continuous low expression level, and with no significant difference between day and night, indicating that the mtf-1 gene expression in the brain of S. chuatsi could be significantly inhibited by cadmium, and the circadian rhythm of mtf-1 in the brain tissue of S. chuatsi is damaged.