The invention discloses a soybean GmFTL3 protein and a soybean GmFTL5 protein which have the amino acid sequence shown in SEQ ID No.1 and the amino acid sequence SEQ ID No.2 respectively or the sequences which are separately obtained through replacing, deleting or adding one or more of amino acid residues and have the same functions. The GmFTL3 and GmFTL5 which are capable of overexpressing soybean flowering genes are used for obviously promoting the flowering of plant (Arabidopsis thaliana), thus the flowering time can be shortened and the growth period can be shortened. The proteins can be used for solving the problem of flowering asynchronism in the hybridization breeding process, the growth period control problems of various crops, vegetable, fruits and flowers, the problem of photoperiod sensitivity and the introduction problem.