The cloning and application of a pleiotropic gene Ghd7 that controls grains yield, heading date and plant height of rice are provided. The gene has the nucleotide sequence as shown in SEQ ID NO: 1. The sequence of the present gene is 3,917 bp in length, contains two exons and encodes 257 amino acids. The cDNA sequence of the gene is as shown in SEQ ID NO: 1. The present gene encodes a protein having the CCT domain of CO protein and having the amino acid sequence as shown in SEQ ID NO: 1. Rice plants transformed with GHD7 gene are obtained using transgenic technology. The transgenic plants all exhibit markedly increased yield, larger number of spikelets per panicle, delayed heading date and elevated plant height as compared to their respective controls (wild type receptors plants). The trait changes are quite consistent with the phenotypes of the two parent genotypes of GHD7 near isogenic lines of Zhenshan 97. The methods for gene cloning, breeding of near isogenic lines and transgene manipulation are also provided, as well as the application of pleiotropic gene GHD7 in research of rice breeding and plant evolution.