Takasugi also joined the Sonno Joi movement with Kogoro KATSURA (Takayoshi KIDO) and Yoshisuke KUSAKA (Genzui KUSAKA) and launched a campaign in Kyoto espousing loyalty to the Emperor, nullification of treaties and the expelling of foreigners, in cooperation with royalists from other clans.
高杉も桂小五郎（木戸孝允）や久坂義助（久坂玄瑞）たちと共にともに尊攘運動に加わり、江戸・京師（京都市）において勤皇・破約攘夷の宣伝活動を展開し、各藩の志士たちと交流した。