The object of this invention is to provide a novel protein that is an Al-activated malate transporter of a plant, and to provide a gene encoding the protein. To deal with this object, present invention provides ALMT1-1 gene, a novel gene derived from wheat, and ALMT1-1 protein encoded by the gene. The ALMT1-1 protein is a protein functioning as aluminum-activated malate transporter. As malate forms complex with Al to inactivate the Al ion, the ALMT1-1 protein is involved in Al tolerance of a plant. Therefore, Al tolerance can be rendered to a plant using the ALMT1-1 gene that encodes the ALMT1-1 protein.