J19 may refer to:
Roads County Route J19 (California) Johor State Route J19, in Malaysia
Vehicles Locomotives GSR Class J19, an Irish steam locomotive LNER Class J19, a British steam locomotive class
Ships , a Halland-class destroyer of the Swedish Navy , a Sandhayak-class survey ship of the Indian Navy
Other uses J19 (journal), a scholarly journal Elongated square cupola, a Johnson solid (J19)