报酬递减（英语：Diminishing returns）亦称为收益递减，报酬递减法则、收益递减法则(Law of Diminishing Returns)、产量递减原则(Principle of Diminishing Marginal Productivity)，边际报酬递减、边际收益递减(Diminishing Marginal Returns)、边际报酬递减法则(Law of Diminishing Marginal Returns)以及边际产量递减法则(Principle of Diminishing Marginal Productivity)等。在经济学中，指在投入生产要素后，每单位生产要素所能提供的产量增加发生递减的现象。

In economics, diminishing returns (also called law of diminishing returns, law of variable proportions, principle of diminishing marginal productivity, or diminishing marginal returns) is the decrease in the marginal (incremental) output of a production process as the amount of a single factor of production is incrementally increased, while the amounts of all other factors of production stay constant.