The invention discloses a sequence of butterfly orchid photoperiod related gene PhalCOL and application, aiming at providing PhalCOL gene, a recombined plant expression vector containing the PhalCOL gene, plant cell line and plant transformant containing the recombined plant expression vector, the application of the PhalCOL gene in promoting the plant vegetative growth and shortening flowering time and a method for detecting expression and distribution of the PhalCOL gene in butterfly orchid plant organization by using in-situ hybridization. The PhalCOL gene of the invention is cloned from butterfly orchid; the overall length of the PhalCOL gene is totally 987bp and decodes the protein of 328 amino acid residues. Experiments show that the gene can influence the growth of the plant, promotes the vegetative growth and reproductive growth of the plant and shortens the flowing time. The gene provides effective technical means for improving the growth course of the plant by the gene engineering, regulating and controlling the flowering phase of the plant, has wide application prospect and enormous economic value.