The present invention relates to an insulinotropic peptide conjugate having improved in-vivo duration of efficacy and stability, comprising an insulinotropic peptide, a non-peptide polymer and an immunoglobulin Fc region, which are covalently linked to each other, and a use of the same. The insulinotropic peptide conjugate of the present invention has the in-vivo activity which is maintained relatively high, and has remarkably increased blood half-life, and thus it can be desirably employed in the development of long acting formulations of various peptide drugs.