たちあがれ日本
Katayama left the LDP when the party set an age limit of 70 for candidates in the House of Councillors proportional representation bloc election in 2010. As a result, he joined the now-defunct Tachiagare Nippon (Sunrise Party of Japan). He was reelected to the upper house for the fifth term in July 2010, representing the Sunrise Party of Japan. He was also the secretary-general of the House of Councillors of the party. Next he became a member of the Nippon Ishin no Kai (Japan Restoration Party), which is led jointly by Tōru Hashimoto and Shintaro Ishihara. He began to represent the party at the House and is a member of the House's committee on general affairs.