A flow divider valve assembly for dividing a flow of fluid between a priority flow device, such as a power steering system, and an excess flow device, such as an auxiliary mechanism. The flow divider valve assembly comprises a valve body defining an inlet port to be connected to a source of fluid under pressure, a priority flow outlet port, an excess flow outlet port and a valve bore interconnecting the ports, and a valve spool axially movable within the valve bore, the valve spool having formed therein an axial bore for permitting a constant communication between the inlet port and the priority flow outlet port. A first restrictor is disposed between the inlet port and the priority flow outlet port and a second restrictor is disposed between the inlet port and the excess flow outlet port. Restriction rate of the first restrictor is made larger than that of the first restrictor.