The present invention provides an agent inducing effector memory T cell or MHC class I for treating or preventing cancer, comprising TLR7 agonist in combination with immune checkpoint inhibitor. And, the present invention also provides a medicament for treating or preventing cancer, comprising TLR7 agonist in combination with immune checkpoint inhibitor.本發明係提供一種含有與免疫檢查點抑制劑併用之TLR7促效劑之用以治療或預防癌的效應記憶型T細胞之誘導劑或MHC I類之誘導劑。又,本發明係提供一種含有與免疫檢查點抑制劑併用之TLR7促效劑的癌之治療劑或預防劑。