筏子或称筏，是用竹、木等平摆着编扎成的水上交通工具，有时也可用牛、羊皮等制囊而成。依不同材质制成而有不同称别：竹制为竹筏、竹排，木制为木筏，皮制成囊为皮船或皮囊筏。

远古人类就观察到单根竹木可以浮在水面上。然而其易翻滚而稳定性差，人也不容易站在上面，于是就发展出了将多根竹子或圆木并排捆绑在一起形成既可载人也可载物的筏，与修整单根木料形成的独木舟。可以说筏子的历史和人类本身的历史一样悠久。

至今，全世界各地仍能看见筏子，广西桂林等地当地人使用的竹筏是有名的旅游项目，乘筏子漂流的运动很多地方都有，一些制筏技巧常成为野营课程的训练项目。另外，在伐木业中常将在上游砍下的原木扎筏漂流到下游的加工厂。

A raft is any flat structure for support or transportation over water. It is the most basic of boat design, characterized by the absence of a hull. Although there are cross-over boat types that blur this definition, rafts are usually kept afloat by using any combination of buoyant materials such as wood, sealed barrels, or inflated air chambers (such as pontoons), and are typically not propelled by an engine.