镊口鱼（学名：Forcipiger longirostris）辐鳍鱼纲鲈形目蝴蝶鱼科的其中一种。

本鱼分布于印度太平洋区，包括留尼旺、科摩罗、也门、马尔代夫、毛里求斯、塞舌尔群岛、斯里兰卡、马来西亚、泰国、菲律宾、印尼、中国南海、东海、日本、**、越南、新几内亚、澳洲、马里亚纳群岛、马绍尔群岛、密克罗尼西亚、帕劳、瑙鲁、纽埃、斐济群岛、夏威夷群岛、法属波里尼西亚、东加、萨摩亚群岛等海域。

Forcipiger longirostris, commonly known as the longnose butterflyfish or big longnose butterflyfish, is a species of butterflyfish found on coral reefs throughout the tropical waters of the Indo-Pacific. Even with its distinctive, point-like long nose, the longnose butterflyfish still can easily be confused with its more common cousin F. flavissimus. Both species may be kept in aquariums.