三角帽（Tricorne）是西洋服饰中的一种男用帽子，由顶部俯视呈三角形而得名。三角帽发源于欧洲，自17世纪后期盛行至18世纪，在极盛期时不但是一般男性知识份子的标准行头，也是军人戎装的标准配件之一。1789年的法国大革命后为双角帽所取代。

三角帽的配戴方法是主尖角在前。

The tricorne or tricorn is a style of hat that was popular during the 18th century, falling out of style by 1800, though actually not called a "tricorne" until the mid 1800s. During the 18th century hats of this general style were referred to as "cocked hats". At the peak of its popularity, the cocked hat (tricorne) varied greatly in style and size, and was worn not only by the aristocracy, but also as common civilian dress, and as part of military and naval uniforms. Typically made from animal fiber, the more expensive being of beaver-hair felt and the less expensive of wool felt, the hat's most distinguishing characteristic was that three sides of the brim were turned up (cocked) and either pinned, laced or buttoned in place to form a triangle around the crown. The style served two purposes: first, it allowed stylish gentlemen to show off the most current fashions of their wigs, and thus their social status; and secondly, the cocked hat, with its folded brim, was much smaller than other hats and therefore could be more easily tucked under an arm when going inside a building, where social etiquette dictated that a gentleman remove his hat. Cocked hats with laced sides could have the laces loosened and the sides dropped down to provide better protection from the weather, sun and rain.