Abstract: The influences of citrate on cell growth and metabolism were investigated in batch cultures of CHO cells.With the addition of citrate,cell growth is inhibited obviously,while the metabolism is changed.In batch cultures with 12 mmol/L citrate,the specific glucose consumption rate of CHO cells is reduced by 37.5%,and the osmolarity increases by 10.0%,the ratios of lactate accumulation to glucose consumption and ammonia accumulation to glutamine consumption increase,compared to those in the medium without citrate.More glutamine was used for energy metabolism through aspartate aminotransferase pathway. CHO cells could be captured in G1 phase by citrate,which could block DNA synthesis,(inhibit) cell growth and induce protein expression.