潮汐能是指从海水面昼夜间的涨落中获得的能量。在涨潮或落潮过程中，海水进出水库带动发电机发电。

潮汐能是一种水能，它将潮汐的能量转换成电能及其它种有用形式的能源。第一座大型潮汐电站（朗斯潮汐电站）于1966年投入使用。

虽然尚未得到广泛应用，潮汐能未来将有潜力发电。潮汐比风能和太阳能具有更强的预测性。在可再生能源的来源中，潮汐能历来都一直受限于高成本和（具有足够高的潮差和流速的）可行地点的局限性，因而进一步限制了其总体可行性。然而，许多新技术在设计（如：动态潮汐能, 潮汐潟湖）和涡轮机技术（如：新式轴流式轮机、双击式水轮机）上的开发和改进，表明潮汐能的总体可行性可以远高于之前的假设，同时经济和环境成本可以降到具有竞争力的水平。

Tidal power, also called tidal energy, is a form of hydropower that converts the energy obtained from tides into useful forms of power, mainly electricity.

Although not yet widely used, tidal power has potential for future electricity generation. Tides are more predictable than wind energy and solar power. Among sources of renewable energy, tidal power has traditionally suffered from relatively high cost and limited availability of sites with sufficiently high tidal ranges or flow velocities, thus constricting its total availability. However, many recent technological developments and improvements, both in design (e.g. dynamic tidal power, tidal lagoons) and turbine technology (e.g. new axial turbines, cross flow turbines), indicate that the total availability of tidal power may be much higher than previously assumed, and that economic and environmental costs may be brought down to competitive levels.