国际贸易，也称通商，是指跨越国境的货品和服务交易，一般由进口贸易和出口贸易所组成，因此也可称之为进出口贸易。国际贸易对很多国家来说是国民生产总值一个重要部分，进出口贸易可以调节国内生产要素的利用率，可以国际间的供求关系，调整经济结构，增加财政收入等。

虽然国际贸易已有悠久历史，但随着近代交通、工业化、跨国企业以及全球化等概念和运作上急速发展，国际贸易对国际的政治、经济和文化都带来了根本的改变。很多情况下，全球化所指涉的实质上就是国际贸易。国际上各方面对国际贸易有着迥异的看法，已发展国家及跨国企业视国际贸易为国际间资源的更有效分配和利用，造福各国人民；另一方面，发展中国家以及非政府组织则认为国际贸易存在着权力上的不平衡，使已发展国家得以透过国际贸易之剪刀差对发展中国家进行剥削。

International trade is the exchange of capital, goods, and services across international borders or territories, which could involve the activities of the government and individual. In most countries, such trade represents a significant share of gross domestic product (GDP). While international trade has been present throughout much of history (see Uttarapatha, Silk Road, Amber Road, salt road), its economic, social, and political importance has been on the rise in recent centuries. It is the presupposition of international trade that a sufficient level of geopolitical peace and stability are prevailing in order to allow for the peaceful exchange of trade and commerce to take place between nations.