叶口蝠科 (学名：Phyllostomidae)，为哺乳纲翼手目的一科，下分48属、148种。著名的吸血蝠就属于该科。

The New World leaf-nosed bats (Phyllostomidae) are found throughout Central and South America, from Mexico to northern Argentina. They are ecologically the most varied and diverse family within the order Chiroptera. Most species are insectivorous, but the phyllostomid bats include within their number true predatory species as well as frugivores (subfamily Stenodermatinae and Carolliinae). For example, the false vampire (Vampyrum spectrum), the largest bat in the Americas, eats vertebrate prey including small dove-sized birds. Members of this family have evolved to use food groups such as fruit, nectar, pollen, insects, frogs, other bats, and small vertebrates, and, in the case of the vampire bats, even blood.