It is intended to identify and provide a novel carnitine transporter gene participating in carnitine transport in the testis and epididymis and carnitine transporter which is a protein encoded by the gene. A protein comprising the amino acid sequence represented by SEQ ID NO: 2 or an amino acid sequence derived therefrom by deletion, substitution or addition of one to several amino acids and being capable of transporting carnitine or its analog; and a gene encoding this protein.