铁路列车，简称列车，俗称火车，是指在铁路轨道上行驶的车辆，通常由多节车厢所组成，可以载运乘客或是货物。

根据《铁路技术管理规程》的定义，列车是“指编成的车列并挂有机车及规定的列车标志。单机、自轮运转特种设备，虽未完全具备列车条件，亦应按列车办理。”

火车的动力来源可以来自个别的铁路机车或是将动力分散到每个车厢的动力分布式列车。19世纪早期的火车的铁路机车以蒸汽机车为主，1910年代起开始更换为柴油机车，较不耗人力，也比较干净，但较复杂及昂贵，后来也逐渐换成电力机车（电力由高架电缆或第三轨提供），客车也开始采用动力分布式列车。其他的动力来源包括马、缆线、重力、气动、电池或是燃气涡轮发动机。火车轨道一般会由二条、三条或是四条铁轨组成，不过也有单轨铁路及不需要轨道的磁悬浮列车。火车一词英文 train 的字根是来自古法语的 trahiner ，此词是来自拉丁文的 trahere ，意思是「拉」。

A train is a form of rail transport consisting of a series of vehicles that usually runs along a rail track to transport cargo or passengers. Motive power is provided by a separate locomotive or individual motors in self-propelled multiple units. Although historically steam propulsion dominated, the most common modern forms are diesel and electric locomotives, the latter supplied by overhead wires or additional rails. Other energy sources include horses, engine or water-driven rope or wire winch, gravity, pneumatics, batteries, and gas turbines. Train tracks usually consist of two running rails, sometimes supplemented by additional rails such as electric conducting rails and rack rails, with a limited number of monorails and maglev guideways in the mix. The word 'train' comes from the Old French trahiner, from the Latin trahere 'pull, draw'.