WORKING MACHINE

A working machine includes: a left traveling motor; a right traveling motor; a left traveling pump including a first pressure-receiving portion and a second pressure-receiving portion; a right traveling pump including a third pressure-receiving portion and a fourth pressure-receiving portion; a traveling operation device configured to apply operation fluid to at least any one of the first, second, third and fourth pressure-receiving portions according to operation of a traveling operation member; an actuation valve configured to supply operation fluid to the traveling operation device, and change a pressure of the operation fluid supplied therefrom to the traveling operation device; a fourth fluid passage fluidly connecting the drainage to the second traveling fluid passage; and a fifth fluid passage fluidly connecting the drainage to the fourth traveling fluid passage.