Both carbon tax and cap-and-trade systems are widely applied to reduce emission. This article compares the clean innovation effects of carbon tax with cap-and-trade systems by a static optimal model. Firstly, both cap-and-trade system and carbon tax stimulates clean innovation and reduce emission. Secondly, cap-and-trade system is more efficient to reduce emission and to promote clean innovation than carbon tax. Finally, firms undertake a loss under carbon tax, while the effects of cap-and-trade system on firms' profits are uncertain, which depends on the carbon cap. In summary, this article supports cap-and-trade system to cope with global climate change, but the regulator should choose the suitable emission cap and carbon trading price to guarantee the efficiency of cap-and-trade system. So, different purposes match with different carbon emission tax policies.

碳税和总量管制与交易制度都广泛用于减少排放。本文通过静态最优模型，将碳税的清洁创新效应与总量控制和交易系统进行了比较。首先，总量控制和交易制度和碳税都刺激了清洁创新并减少了排放。第二，总量管制和交易制度比碳税更有效地减少排放和促进清洁创新。最后，企业根据碳税承担亏损，而总量管制和交易制度对企业利润的影响尚不确定，这取决于碳排放上限。综上所述，本文支持总量管制和交易制度以应对全球气候变化，但监管机构应选择合适的排放上限和碳交易价格，以保证总量管制和交易制度的效率。所以，