Based on the protein comparison between zebrafish G li2 and fruit fly Ci and the analysis of hydrophilicity/hydrophobicity of G li2 protein by computer programmer, the recombination N-terminal partial protein of G li2 protein was designed. After the DNA fragment encoding the N terminal part was cloned out by PCR, it was ligated with an expression vector containing H is-tag and transformed into BL-21, a bacteria l expression strain, to express this protein. After the expression condition was optimized, the protein can be expressed at high level after having been induced for 3 hours when the inducer— IPTG was at 0.6mmol /L. The protein is soluble in solution, a bacterial protein extraction solution. After the protein solution was diluted in B-per solution, the recombination protein can bind to the Ni-NTA column and be purified highly.