[Objective] To investigate the possibilities of expressing bovine PrP27-30 gene in CHO-K1 cells. [Method] The purified PCR products of PrP27-30 were digested and ligated to the pCI-neo vector to yield pCI-neo-PrP27-30 that was used as an expression vector. Then CHO-K1 cells were transfected by pCI-neo-PrP27-30, and stable expression clone cells were screened by methotrexate (MTX) at a concentration of 0.1 and 1.0 umol/L. The transient expression was detected by indirect immunofluorescence assay and western blot. [ Result] After drug selection with MTX, the expression of PrP27-30 gene was detected in CHO-K1 cells. [Conclusion] Recombinant protein PrP27-30 expressed in CHO-K1 cells has better immunoreactivity and can be used to study secondary structure and regulation mechanism of pathological isoform of prion protein (prpC).