ST4 or ST-4 may refer to:

The Monospar ST-4, a variant of the Monospar aircraft, built by British aircraft manufacturer General Aircraft Limited. The Snow Trac ST4, a model in the Snow Trac family of Snowcat vehicles. The Ducati ST4s, a motorcycle manufactured by Ducati. Star Trek IV: The Voyage Home, a science fiction film in the Star Trek series. Starship Troopers: Invasion, fourth entry in the Starship Troopers film series. A popular Autoguider port in amateur astronomy

See also STIV (disambiguation)