Objective: To investigate degradation kinetics of main ingredients (salvianolic acid B and rosmarinic acid) of salvianolate lyophilized injection under different pH and temperatures. Method: HPLC was adopted to determine the content of salvianolic acid B and rosmarinic acid at different pH values and temperatures

degradation kinetic parameters of these two ingredients were evaluated by chemical kinetics. Result: Reaction of salvianolic acid B and rosmarinic acid at different pH values and temperatures were accord with the first-order kinetics

degradation rate accelerated by increasing of pH value and temperature.According to arrhenius equation

activation energy (Ea) of salvianolic acid B in aqueous solution and salvianolate lyophilized injection were 48.54

95.19 kJ·mol-1

respectively.Ea of rosmarinic acid in aqueous solution and salvianolate lyophilized injection were 49.83

83.56 kJ·mol-1

respectively. Conclusion: Salvianolic acid B and rosmarinic acid were sensitive to strong alkaline and high temperature conditions

but salvianolate lyophilized injection could obviously improve their stability.