A breeches role (also pants role or trouser role, or Hosenrolle) is one in which an actress appears in male clothing. Breeches, tight-fitting knee-length pants, were the standard male garment at the time these roles were introduced. The theatrical term travesti covers both this sort of cross-dressing and also that of male actors dressing as female characters. Both are part of the long history of cross-dressing in music and opera and later in film and television.

In opera, a breeches role refers to any male character that is sung and acted by a female singer. Most often the character is an adolescent or a very young man, sung by a mezzo-soprano or contralto. The operatic concept assumes that the character is male, and the audience accepts him as such, even knowing that the actor is not. Cross-dressing female characters (e.g., Leonore in Fidelio or Gilda in Act III of Rigoletto) are not considered breeches roles. The most frequently performed breeches roles are Cherubino (The Marriage of Figaro), Octavian (Der Rosenkavalier), Hansel (Hansel und Gretel) and Orpheus (Orpheus and Euridice), though the latter was originally written for a male singer, first a castrato and later, in the revised French version, an haute-contre.

Because non-musical stage plays generally have no requirements for vocal range, they do not usually contain breeches roles in the same sense as opera. Some plays do have male roles that were written for adult female actors, and (for other practical reasons) are usually played by women (e.g., Peter Pan); these could be considered modern-era breeches roles. However, in most cases, the choice of a female actor to play a male character is made at the production level; Hamlet is not a breeches role, but Sarah Bernhardt once played Hamlet as a breeches role. When a play is spoken of as "containing" a breeches role, this does mean a role where a female character pretends to be a man and uses male clothing as a disguise.