Masatada Tsuchiya (土屋 正忠 Tsuchiya Masatada) is a Japanese politician who has been a member of the House of Representatives of Japan since the September 2005 general election. He resigned his position as mayor of Musashino, Tokyo in order to run against the Deputy President of the Democratic Party of Japan, Naoto Kan, for the seat of Tokyo Constituency No. 18. Although he lost in the run-off, he was still elected under the party-list proportional representation system. At age 63, he was the oldest among the 83 currently serving Liberal Democratic Party members upon election.