The adherent cultured CHO cells were screened and domesticated to obtain high expression of cell suspension culture for production of recombinant human erythropoietin erythropoietin (rHuEPO). 96-Well and 24-well plates culture method was used to screen and domesticate the highly expressing CHO cell strain. The high expression cell strain was acclimated and it was made suitable for suspension culture. It's inoculated into the bioreactor in serum-free culture after amplified by the shake flask, and glucose content and daily rHuEPO expression were detected. The suspension culture of CHO cell production of rHuEPO had short production period, higher expression than adherent culture. On the other hand, it was easy to operate and scale-up, but not easy to pollute. Furthermore, we established the CHO cell strain for suspension culture, which provided a tech. basis for industrial production of CHO cells the rHuEPO. After process optimization, the use of serum-free suspension culture production of erythropoietin average expression has high, short production period, low cost of production than adherent culture.