The invention provides a promoter for promoting a specific expression of amylose synthetase gene GBSSI-3 in banana fruits and application of the promoter. A nucleotide sequence of the promoter is as shown in SEQ ID NO.1, and the promoter is capable of guiding specific expression of the amylose synthetase gene GBSSI-3 in fruits instead of roots, stems and leaves. By cloning and functional study on the GBSSI-3 promoter, part of functions and promotion activity of the promoter can be determined, and theoretical bases can be provided for researches on the sequence of the banana GBSSI-3 gene promoter; a candidate fruit specific promoter is provided for development and application of tissue specific promoters, increase of amylose content of the banana fruits by means of genetic engineering and improvement of amylose quality; theoretical bases are provided for clarification of a whole starch synthesis and regulation network, and a candidate fruit specific promoter is provided for meeting the requirement on diversification of starch different in straight/branch chains.