S34

S34 may refer to:

Aviation

 * Blériot-SPAD S.34, a French biplane
 * Plains Airport, in Sanders County, Montana, United States
 * Sikorsky S-34, an American sesquiplane
 * Skyfly S-34 Skystar, a Swiss ultralight

Naval vessels

 * BRAZILIAN SUBMARINE Tikuna
 * SMS S34 (1914), a torpedo boat of the Imperial German Navy
 * SPANISH SUBMARINE Cosme García
 * USS S-34 (SS-139), a submarine of the United States Navy

Other uses

 * County Route S34 (California)
 * Sulfur-34, an isotope of sulfur