A driving device (105, 105A, 105B) for a work machine, comprising: a plurality of closed circuits (A, B, C, D) including a plurality of closed-circuit hydraulic oil outflow/inflow control sections (12, 14, 16, 18) having two outflow/inflow ports enabling the outflow/inflow of hydraulic oil in both directions, and at least one single rod hydraulic cylinder (1, 3, 5) having a first hydraulic oil chamber (1a, 3a, 5a) and a second hydraulic oil chamber (1b, 3b, 5b); a plurality of closed-circuit switching control sections (43a-43d, 45a-45d,47a-45d,49a-49d) that switch supply of the hydraulic oil to the at least one single rod hydraulic cylinder (1, 3, 5) connected to any of the plurality of closed-circuit hydraulic oil outflow/inflow control sections(12, 14, 16, 18) to form the closed circuit; a plurality of open circuits including a plurality of open-circuit hydraulic oil outflow/inflow control section (13, 15, 17, 19) having an inflow port in which hydraulic oil flows from a tank, and an outflow port from which hydraulic oil flows out, and a plurality of open-circuit switching sections (44a-44d, 46a-46d, 48a-48d, 50a-50d) connected to the outflow ports of the plurality of open-circuit hydraulic oil outflow/inflow control sections (13, 15, 17, 19); a controller that controls the plurality of the closed-circuit hydraulic oil outflow/inflow control sections (12, 14, 16, 18), the plurality of closed-circuit switching control sections (43a-43d, 45a-45d,47a-45d,49a-49d), the plurality open-circuit hydraulic oil outflow/inflow control sections (13, 15, 17, 19) and the plurality of the open-circuit switching sections (44a-44d, 46a-46d, 48a-48d, 50a-50d); characterized in that, a plurality of connection passages (301, 302, 303, 304) branched from a hydraulic cylinder connection passage for independently connecting the at least one single rod type hydraulic cylinder (1, 3, 5) to any of the plurality of open circuit switching sections (44a-44d, 46a-46d, 48a-48d, 50a-50d), the controller, based on an operation signal output, switches any of the plurality of open-circuit switching sections (44a-44d, 46a-46d, 48a-48d, 50a-50d) between a conduction state and an cutoff state, whereas any of the plurality of open-circuit switching sections (44a-44d, 46a-46d, 48a-48d, 50a-50d) supply destination of the hydraulic fluid outflowing from the plurality of open-circuit hydraulic oil outflow/inflow control sections (13, 15, 17, 19) to one of the plurality of connection passages (301, 302, 303, 304). a plurality of closed circuits (A, B, C, D) including a plurality of closed-circuit hydraulic oil outflow/inflow control sections (12, 14, 16, 18) having two outflow/inflow ports enabling the outflow/inflow of hydraulic oil in both directions, and at least one single rod hydraulic cylinder (1, 3, 5) having a first hydraulic oil chamber (1a, 3a, 5a) and a second hydraulic oil chamber (1b, 3b, 5b); a plurality of closed-circuit switching control sections (43a-43d, 45a-45d,47a-45d,49a-49d) that switch supply of the hydraulic oil to the at least one single rod hydraulic cylinder (1, 3, 5) connected to any of the plurality of closed-circuit hydraulic oil outflow/inflow control sections(12, 14, 16, 18) to form the closed circuit; a plurality of open circuits including a plurality of open-circuit hydraulic oil outflow/inflow control section (13, 15, 17, 19) having an inflow port in which hydraulic oil flows from a tank, and an outflow port from which hydraulic oil flows out, and a plurality of open-circuit switching sections (44a-44d, 46a-46d, 48a-48d, 50a-50d) connected to the outflow ports of the plurality of open-circuit hydraulic oil outflow/inflow control sections (13, 15, 17, 19); a controller that controls the plurality of the closed-circuit hydraulic oil outflow/inflow control sections (12, 14, 16, 18), the plurality of closed-circuit switching control sections (43a-43d, 45a-45d,47a-45d,49a-49d), the plurality open-circuit hydraulic oil outflow/inflow control sections (13, 15, 17, 19) and the plurality of the open-circuit switching sections (44a-44d, 46a-46d, 48a-48d, 50a-50d); characterized in that, a plurality of connection passages (301, 302, 303, 304) branched from a hydraulic cylinder connection passage for independently connecting the at least one single rod type hydraulic cylinder (1, 3, 5) to any of the plurality of open circuit switching sections (44a-44d, 46a-46d, 48a-48d, 50a-50d), the controller, based on an operation signal output, switches any of the plurality of open-circuit switching sections (44a-44d, 46a-46d, 48a-48d, 50a-50d) between a conduction state and an cutoff state, whereas any of the plurality of open-circuit switching sections (44a-44d, 46a-46d, 48a-48d, 50a-50d) supply destination of the hydraulic fluid outflowing from the plurality of open-circuit hydraulic oil outflow/inflow control sections (13, 15, 17, 19) to one of the plurality of connection passages (301, 302, 303, 304).