WORKING FLUID SUPPLY SYSTEM

A working fluid supply system (100) is provided with: a first oil pump (10) and a second oil pump (11) driven by an engine (50); a switching valve (24) configured to cause a discharge passage (17) of the second oil pump (11) to communicate with at least one of a supply passage (14) and a first drain passage (20); and a controller (40) configured to switch the switching valve (24). The controller (40) is configured to switch the switching valve (24) by spending a switching time that is set in accordance with a degree of pressure variation predicted to be caused in the supply passage (14) when the switching valve (24) is switched instantaneously.