Disclosed are: a substance transfer carrier to an extracellular matrix-producing cell in the lung, which comprises a retinoid; a therapeutic agent for fibroid lung, which utilized the carrier; and a preparation kit of the therapeutic agent.本發明係關於一種肺中的細胞外間質生成細胞用之物質輸送用攜帶體、應用該攜帶體的肺纖維化症治療劑、及該治療劑的製備套組,其中該攜帶體係含有類視色素(retinoid)。