摘要：Using the Stackelberg differential games(SDG) theory,we quantitatively study a problem of optimal intertemporal investment and tax rate *** some appropriate assumptions,the open-loop Stackelberg equilibrium solutions are *** solutions show that:*** optimal strategies derived from differential game and unilateral optimal control approaches are different;*** is not always the best strategy for the government to use a constant tax rate over the whole time period;*** admissible size of tax rate adjustment may have great effect on the government's optimal strategy;*** approach has no significant effect on the firm's optimal investment strategy.