通货膨胀（英语：inflation，在**简称通膨，大陆为通胀）本意为货币流通数量增加，但也指向物价水准在某一时期内，连续性地以相当的幅度上涨，也就是物价上升的现象，或直接指物价上涨。「通货」意指流通的货币，通货膨胀指货币发行数量上升，而物价上涨是因需求增加或供给减少，两者关联为货币发行数量上升投入消费，「太多的货币追逐太少的商品」而使得物价上涨，而现在人们经常直接使用「通货膨胀」一词来表示「物价上升」的现象。而货币发行数量上升，不一定使物价上升，因为可能尚未投入消费，或是被更多的商品（服务）生产或科技进步所抵消，而某些情况，比如说，若新发行的货币是流向生产端扩充产能，反而可能造成供过于求，物价反而会下跌，形成货币发行数量增加但物价却下跌，与常识相悖的经济现象。

In economics, inflation is a sustained increase in the general price level of goods and services in an economy over a period of time.

When the price level rises, each unit of currency buys fewer goods and services. Consequently, inflation reflects a reduction in the purchasing power per unit of money – a loss of real value in the medium of exchange and unit of account within the economy. A chief measure of price inflation is the inflation rate, the annualized percentage change in a general price index, usually the consumer price index, over time. The opposite of inflation is deflation.