A drive system for a self-propelled harvesting machine includes a drive engine, designed as an internal combustion engine, a transfer gearbox driven by the drive engine that includes a first driven pulley which is disposed on a drive shaft for driving at least one drive pulley of a working mechanism using a first belt, and at least one hydraulic pump for driving a further working mechanism. A second output pulley is assigned to the transfer gearbox and drives the at least one hydraulic pump using a second belt.