巨尾鱼科（学名：Giganturidae）俗称远视鱼或管眼仙鱼，英文通称望远镜鱼（Telescopefish），是辐鳍鱼纲仙女鱼目的其中一科，其下只有一属巨尾鱼属（学名：Gigantura）。其属名是以 gigant（希腊文：巨大）+ oura（希腊文：尾）构成，即「巨大的尾」之意。

巨尾鱼科的鱼类主要分布于热带至亚热带海域，范围包括太平洋、大西洋与印度洋三座主要的洋。为深海鱼的一种，主要生活于深海的中层带（根据出现纪录统计，生活的水域深度约 17 至 3000 公尺深，但通常在 500 到 3000 公尺深的深海中较为常见）。

Telescopefish are small, deep-sea aulopiform fish comprising the small family Giganturidae. The two known species are within the genus Gigantura. Though rarely captured, they are found in cold, deep tropical to subtropical waters worldwide.

The common name of these fish is related to their bizarre, tubular eyes. The genus name Gigantura refers to the Gigantes, a race of giants in Greek mythology—coupled with the suffix oura, meaning "tail", thus Gigantura refers to the greatly elongated, ribbon-like lower half of the tailfin that may comprise over half of the total body length.