It is intended to provide novel amino acid transporters which act as a single molecule and transport neutral amino acids typified by branched amino acids, and genes thereof. A protein consisting of an amino acid sequence represented by SEQ ID NO:2, 4, 6 or 8 or an amino acid sequence derived from an amino acid sequence represented by SEQ ID No:2, 4, 6 or 8 by deletion, substitution or addition of one to several amino acids, and being capable of sodium-independently transporting neutral amino aicds typified by branched amino acids and analogs thereof as a single molecule. A gene which is a DNA consisting of a base sequence represented by SEQ ID NO:1, 3, 5 or 7 or a DNA hybridizable with it and encodes a protein capable of sodium-independently transporting branched amino acids as a single molecule.