In 2006, Takagi became an assistant coach under the manager Yusuke Adachi at J2 League club Yokohama FC. In March, Adachi was sacked for poor performance and Takagi became a new manager. The club won the champions in 2006 and was promoted to J1 League from 2007. However the club results were bad in J1 and he was sacked in August. In 2008, he became an assistant coach under the manager Tetsuji Hashiratani at J1 club Tokyo Verdy. The club was relegated to J2 end of 2008 season and Takagi became a new manager as Hashiratani successor from 2009. However Takagu was sacked in October. In 2010, he signed with J2 club Roasso Kumamoto and managed the club until 2012. In 2013, he moved to his local club V-Varen Nagasaki which was promoted to J2 from 2013. The club won the 2nd place in 2017 and was promoted to J1 from 2018. However the club finished at the bottom place in 2018 and was relegated to J2 in a year. He also resigned end of 2018 season. In 2019, he signed with J2 club Omiya Ardija and managed the club until 2020.