服勤员（Train Attendant），此处系指铁路列车上，负责车上贩卖、旅客服务、监控车载设备状态，及紧急时协助列车长之列车组员。

在台铁，车上贩卖的服勤员（服务员）是不负责安全相关工作的。不过于紧急应变时仍应受列车长指挥。

在**的服勤员，主要工作范围包含：商务车厢服务、车上贩卖服务、旅客咨询与服务、协助行动不便旅客、监控列车上各项服务设备运作状况，故障时通知列车长，以及紧急状况时协助列车长疏散旅客等。

A car attendant is a railroad employee placed in charge of a single coach, sleeping car, or lounge car on a medium-to-long-distance passenger train.

Their duties vary according to the type of car, but most typically include managing passenger seat assignments (in order to avoid separating parties of two or more), assisting the conductor with tickets, making announcements, opening and closing doors, assisting passengers with boarding and detraining, monitoring the safe operation of onboard systems, and generally ensuring the safe operation of the car. In addition, sleeping car attendants (formerly called "Pullman porters") typically convert the individual accommodations from "day" mode to "night" mode, rather than leaving that to the passengers, and set out coffee and juice for their passengers each morning. (Sleeping car attendants, however, typically have fewer passengers to serve than coach attendants). Lounge car attendants typically operate food and beverage service, sell souvenirs and other non-food items, operate onboard motion picture service, and keep tables clean.