A liquid discharge device includes: a head in which an ejection port to eject liquid as a droplet is formed; a buffer tank which is connected with the head through a supply channel and a collection channel and in which the liquid is housed; a deaeration module which is provided on the side of the supply channel; and a main tank in which the liquid supplied to the buffer tank through the supplement channel is stored, where: the supply channel is connected with a side surface of the buffer tank; the supplement channel penetrates the side surface of the buffer tank and has an exit of the supplement channel in the buffer tank; and the liquid supplied from the supplement channel has speed when the liquid collides with an inner wall surface of the buffer tank facing the exit of the supplement channel.