制造业（或制造工程，亦称为工业）是利用方法生产产品以供销售，方法可能会使用机器、工具、化学或生物进程或是配方，制造可以泛指不同程度的人力投入，可以从手工艺到高科技，但多半是指工业化的生产，也就是大量的将原物料制造成成品，成品可能被制成其他东西或更复杂的产品，像是飞机、家电或汽车等，成品也可能卖给批发商，批发商再将货品卖给零售商，最后再卖给消费者。

制造业会在所有类型的经济系统下出现。自由市场经济的制造业通常会量产产品，销售给消费者赚取利润。集体主义下的制造业一般是由中央计划的计划经济所控管。混合型的经济体中，制造业一般会受到某种程度的法规限制。

Manufacturing is the production of merchandise for use or sale using labour and machines, tools, chemical and biological processing, or formulation. The term may refer to a range of human activity, from handicraft to high tech, but is most commonly applied to industrial production, in which raw materials are transformed into finished goods on a large scale. Such finished goods may be used for manufacturing other, more complex products, such as aircraft, household appliances or automobiles, or sold to wholesalers, who in turn sell them to retailers, who then sell them to end users and consumers.