李嘉图等价命题（英语：Ricardian equivalence proposition），又称为巴罗－李嘉图等价定理（英语：Barro-Ricardo equivalence theorem），经济学上的一个假说。这个假说认为，在理性预期假说成立的前提下，一个理性的消费者会把政府的预算限制，内化到自己的消费行为去，因此，改变徵税的时机，完全不会影响消费者的支出水准。李嘉图等价命题认为，无论政府使用租税手段，或是以债券方式借贷，整个经济体的需求水准，都会保持不变，因此对于经济不会有任何影响。

The Ricardian equivalence proposition (also known as the Ricardo–De Viti–Barro equivalence theorem) is an economic hypothesis holding that consumers are forward looking and so internalize the government's budget constraint when making their consumption decisions. This leads to the result that, for a given pattern of government spending, the method of financing that spending does not affect agents' consumption decisions, and thus, it does not change aggregate demand. Thus, this theorem is used as an argument against tax cuts and spending increases aimed to boost aggregate demand.