The invention discloses an associated protein of biology cadmium resistance and coding gene of the same. The protein in the invention is the following protein (a) or (b), wherein protein (a) comprises amino acids according to amino acid sequence as shown in sequence 1 of a sequence table, and protein (b) is protein derived from the sequence 1, with the amino acid sequence of the sequence 1 undergoing replacement and/or miss and/or addition of one or several amino acid residues and with the amino acid sequence associated with biology cadmium resistance. The invention also protects coding gene of the protein and expression box, recombination expression vector, transgenic cell lines or recombinant bacterium which contain the coding gene. The resistance of recombinant bacterium with the coding gene to high density cadmium (1mMCdCl2) is proved by experiments to be obviously enhanced. The invention can be applied to cultivate cadmium-resistant recombinant bacterium or cadmium-resistant transgenic plants, which has significant meanings.