U20

U20 or U-20 may refer to:

Naval vessels

 * GERMAN SUBMARINE U-20
 * HMS Snipe (U20), a sloop of the Royal Navy
 * SM U-20, a submarine of the Austro-Hungarian Navy

Other uses

 * Great truncated cuboctahedron
 * Meizu U20, a smartphone
 * Roland U-20, a synthesizer
 * Small nucleolar RNA SNORD20
 * U20 summit, an international summit for cities from the G-20 countries
 * Under-20 athletics
 * Uppland Runic Inscription 20