Abstract: The aim was to analyze the effect of exogenous putrescine on hormone and flavonoid accumulation in Betula platyphylla suspension cultured cells. Various concentrations of putrescine and exogenous hormone were added to the eight-day-old suspension cultured cells, the content of flavonoid, ABA, JA, IAA and ZR were analyzed by UV spectrophotometer and ELISA. Both exogenous putrescine and hormone treatment increased the content of flavonoid in birch suspension cultured cells. Among them, the highest flavonoid content was induced by 1 mmol/L putrescine for 24 h, the increasing rate was 97.90% . Among the hormone treatment, the highest flavonoid content was induced by 1 mg ABA induction for 24 h, the increasing rate was 103.40%. The joint treatment of putrescine and hormone increased much more flavonoid content than that of control or putrescine treatment. The highest flavonoid content was induced by 1 mmol/L putrescine and 5 mg/L JA, the increasing rate was 197.43% and 103.57% compared with control and putrescine treatment, respectively. At the same time, putrescine increased the content of IAA and ZR, but decreased the content of ABA and JA. To further analyze the correlation, we found the correlation between hormones or hormone ratio with flavonoid content was different, JA treatment showed the highest change from -0.883 to 0.903. It can be inferred that the interaction between putrescine and hormone (ABA, JA, IAA and ZR) regulated the flavonoid production in Betula platyphylla suspension cultured cells.