The invention discloses protein related to low nitrogen stress and high salt stress resistance and a coding gene and application of the protein. The provided protein is: a) protein with the amino acid sequence shown as the sequence 1; b) fusion protein with a label connected to the N terminal and/or C terminal of the protein shown as the sequence 1; and c) protein obtained by replacing and/or deleting and/or adding one or several amino acid residues to the amino acid sequence shown as the sequence 1 and having the same function. It is shown by the test that the provided ZmCCT gene can increase the ratio of resistant plants with low nitrogen stress and high salt stress resistance in offsprings of ZmCCT transgenic plants, and the ratio of ZmCCT transgenic positive plants to negative plants in offsprings, and greatly improves the resistance to fusarium graminearum stem rot.