Abstract: To elucidate the role of plant protein phosphatase 2C (PP2C) in the symbiotic interaction between leguminous plants and rhizobia, a protein phosphatase gene GmPP2C28 from soybean was cloned and its encoded protein was subcellular localized. Subsequently, the recombinant protein was expressed and purified in Escherichia coli. In addition, the expression patterns of GmPP2C28 gene in different tissues and roots at different stages after inoculation with rhizobia were analyzed using fluorescence quantitative PCR technology. The results showed that the cDNA sequence length of the complete coding region of GmPP2C28 was 1029 bp, encoding 343 amino acids, and its coding protein was located in the nucleus of Arabidopsis protoplasts. The recombinant protein in vitro was highly expressed in soluble form. The target band size of the purified GmPP2C28 protein was about 37 kD. The expression level of GmPP2C28 gene was relatively high in the root and nodule of soybean, and the expression level showed a pattern of first increasing and then decreasing in the root of soybean after inoculation with rhizobia.