A liquid target device includes a liquid accommodation portion in which a target liquid is accommodated, a beam passage through which a charged particle beam emitted from a particle accelerator passes to reach the liquid accommodation portion, a target foil that separates the beam passage and the liquid accommodation portion from each other, and a vacuum foil that separates a vacuum region provided upstream of the beam passage and the beam passage from each other. The beam passage is provided with a first gas chamber into which a cooling gas is supplied at a position on the vacuum foil side and a second gas chamber into which a cooling gas is supplied at a position closer to the target foil side than the first gas chamber and the first gas chamber and the second gas chamber are separated from each other by an intermediate foil.