The invention discloses a recombinant goose interleukin-2(gsIL-2) protein preparing method and its use. The DNA fraction of RT-PCR amplified Zhedong white goose interleukin-2, prokaryotic expression carrier pBAD/HisB, and eukaryotic expression carriers pMET alpha B and pMETB compose expression particles pBAD/HisB/gsIL-2, pMET alpha B/gsIL-2 and pMETA/gsIL-2, which are converted to Escherichia coli LMG194, microzyme PMAD11 and PMAD16, respectively, then inducing expression. After inducing, making ultrasonic wave cracking and deposit elimination by centrifugation on Escherichia coli and microzyme PMAD16 to obtain crude products of gsIL-2 protein, PMAD11 expressed gsIL-2 is mainly separated in the culture medium, centrifugating and taking supernatant to obtain gsIL-2 protein crude products. Using Ni-NTAArgarrose protein purifying system, thus able to faster obtain gsIL-2 pure product, and the crude and pure products can act as immune assistant and disease-curing drugs. It applied genetic engineering technique to prepare recombinant protein gsIL-2, and has simple technical flow, low production cost, good stability, high bioactivity and other characters.