ZL
ZL may refer to:

Aviation 
 Hazelton Airlines (1953–2001; IATA: ZL)
 Rex Airlines (founded 2002; IATA: ZL)
ZL, an unused aircraft registration prefix for New Zealand

Science, technology and mathematics 
 ZL, ITU prefix for New Zealand, in radio and television
 Zorn's lemma, a proposition in set theory
 ZL, a Mazda Z5 engine variant

Other uses 
 Polish zloty (sign: zł), the currency of Poland
 z"l, an honorific for the dead in Judaism
 ZL, assistant (with ZR and ZY) of Golden Age superhero Masked Marvel (Centaur Publications)