Foreign substance introduction method provided by the present invention, the amino acid sequence: WRRQARFK (SEQ ID NO: 1) or one or two or three amino acid residues of the amino acid sequence substitutions, deletions and / or additions ( a carrier peptide fragment consisting of any amino acid sequence that is formed by being inserted), and the foreign substance of interest bound to the N-terminal and / or C-terminal of said carrier peptide fragments, for foreign substance introduction construct having a step of preparing, the foreign substance introduction construct was incubated with feeding in a sample comprising the eukaryotic cell of interest, the sample to which the foreign substance introduction constructs were fed, in the sample and it includes the step of introducing the construct into a eukaryotic cell.本発明によって提供される外来物質導入方法は、アミノ酸配列:WRRQARFK(配列番号1)若しくは該アミノ酸配列のうちの1個又は2個又は3個のアミノ酸残基が置換、欠失及び/又は付加(挿入)されて形成されたアミノ酸配列の何れかから成るキャリアペプチドフラグメントと、該キャリアペプチドフラグメントのN末端側及び/又はC末端側に結合した目的の外来物質と、を有する外来物質導入用構築物を用意する工程と、前記外来物質導入用構築物を、目的とする真核細胞を含む試料中に供給する工程と、前記外来物質導入用構築物が供給された前記試料をインキュベートして、前記試料中の真核細胞内に前記構築物を導入する工程とを包含する。