Cafius bistriatus is a species of relatively large rove beetle in the family Staphylinidae.

[1][2] It can be found from Quebec and Newfoundland to Florida but not yet in South Carolina or Georgia, and in Texas.

In the Caribbean, it occupies Antigua and Barbuda (Antigua), Barbados, Dominica, Dominican Republic, Grenada (Carriacou), Guadeloupe, Jamaica, Montserrat, Puerto Rico (including Mona), St. Kitts-Nevis (St. Kitts), St. Lucia, Trinidad & Tobago (both islands), and U.S. Virgin Islands (St. Thomas).

In eastern Mexico, it occurs in Veracruz, Campeche and Quintana Roo.

Synonym Philonthus bilineatus Erichson, 1840, All of the specimens seen from Atlantic coasts, including the Gulf of Mexico and the Caribbean Sea belong to this, the typical subspecies.