折梯，是土木工程用品，协助工作人员在工地上高落低，有如活动楼梯。折梯用时打开，用完折合起来，方便转移。

在从前，战争时代的攻城防守战，折梯也大派用场，跨越敌方的城墙。 而守护的一方，必须尽快把靠近的折梯推倒，免得对方沿梯爬上来。

现在，折梯在建筑工程用品商店有售，分为大、中、细码标准尺寸。 不过，为要求，用家有特别度身订造「超长版」，或者自制木折梯。

折梯的代用品是清洁工司常用的组件式折合架，甚至是长臂猿式工程车，它们都比较折梯安全，不容易翻倒引发工伤或死亡风险。

为工业安全，用折梯高空工作，当局有操作指引，要求工人配带安全带，并且必须有助手在折梯下接应，防止折梯重心不平衡。

A ladder is a vertical or inclined set of rungs or steps. There are two types: rigid ladders that can be leaned against a vertical surface such as a wall, and rope ladders that are hung from the top. The vertical members of a rigid ladder are called stringers or rails (US) or stiles (UK). Rigid ladders are usually portable, but some types are permanently fixed to buildings. They are commonly made of metal, wood, or fiberglass, but they have been known to be made of tough plastic.