The present invention relates to a fusion polypeptide containing a glucagon-like peptide (GLP) and an immunoglobulin hybrid Fc, and more specifically, to a fusion polypeptide with an increased half-life and improved efficacy compared to the conventional fusion polypeptide based on the discovery of an immunoglobulin hybrid Fc suitable for GLP or analogs thereof, and a pharmaceutical composition for treating diabetes, inflammatory bowel disease, endoenteritis or diarrhea caused by anticancer chemotherapy, or short bowel syndrome, containing the fusion polypeptide. The fusion polypeptide of the present invention has an increased half-life and improved resistance to DPP-4 enzyme compared to those of GLP-1 and GLP-2, and it thus has improved drug efficacy in treating diabetes, inflammatory bowel disease, endoenteritis or diarrhea caused by anticancer chemotherapy, or short bowel syndrome, compared to those of the conventional drugs. Accordingly, the fusion polypeptide of the present invention can be effectively applied to pharmaceutical drugs.