The present invention relates a method of preparing a Glucagon-like peptide 2 (GLP-2) analog by gene recombination. The present invention provides an expression vector, which includes: (a) a nucleic acid sequence encoding tag protein; (b) a nucleic acid sequence encoding Smt3 protein (SEQ ID NO: 1); and (c) a nucleic acid sequence encoding linker peptide (SEQ ID NO: 2) and GLP-2 analog. The fusion protein expressed by the expression vector can be cleaved by thrombin, wherein the cleaving position is at the linker peptide, and then the GLP-2 analog is produced.