PTN

PTN may refer to:
 * Harry P. Williams Memorial Airport (IATA/FAA code PTN)
 * Paramount Television Network (1948–1956), U.S.
 * Partido Trabalhista Nacional (National Labour Party) - a mid-ranking party of the Fourth Brazilian Republic, best known as the party of Jânio Quadros from 1954 to 1965
 * Partido Trabalhista Nacional (National Labor Party), former name of Podemos (Brazil)
 * Pleiotrophin, a protein