A power unit (1, 101) comprising: first and second drive sources (E, M) each of which outputs rotational power to a drive target other than pumps; a first pump rotationally driven by the rotational power of the first drive source; a second pump rotationally driven by the rotational power of the first and second drive sources (E, M), the second pump being different form the first pump; and a power transmission structure (21, 121) that transmits the rotational power of the first drive source to the first pump and that transmits the rotational power of the first and second drive sources (E, M) to the second pump, wherein the first drive source is an engine and the second drive source is an electric motor; wherein the power transmission structure (21, 121) includes transmission components, a first input shaft that inputs the rotational power of the first drive source to the first pump, and a second input shaft that inputs the rotational power of the first and second drive sources (E, M) to the second pump, wherein the power transmission structure (21, 121) transmits the rotational power to the first pump through one transmission component of the transmission components and to the second pump through another transmission component of the transmission components; wherein the first pump is a pressure transmission pump that supplies a pressure transmission fluid to a pressure transmission target to drive the pressure transmission target; wherein the second pump is a lubrication pump that supplies a lubricating fluid to a lubrication target to lubricate the lubrication target; wherein the second pump is configured to be driven by any one of the first and second drive sources (E, M) even in case that the other one of the first and second drive sources (E, M) is stopped, wherein one of the first and second input shafts (S3, S4) is inserted into the other of the first and second input shafts (S3, S4) and rotatable about a rotational axis relative to the other of the first and second input shafts (S3, S4), and wherein the power unit (1, 101) further comprises different flow paths through which the lubricating fluid and the pressure transmission fluid respectively flow. first and second drive sources (E, M) each of which outputs rotational power to a drive target other than pumps; a first pump rotationally driven by the rotational power of the first drive source; a second pump rotationally driven by the rotational power of the first and second drive sources (E, M), the second pump being different form the first pump; and a power transmission structure (21, 121) that transmits the rotational power of the first drive source to the first pump and that transmits the rotational power of the first and second drive sources (E, M) to the second pump, wherein the first drive source is an engine and the second drive source is an electric motor; wherein the power transmission structure (21, 121) includes transmission components, a first input shaft that inputs the rotational power of the first drive source to the first pump, and a second input shaft that inputs the rotational power of the first and second drive sources (E, M) to the second pump, wherein the power transmission structure (21, 121) transmits the rotational power to the first pump through one transmission component of the transmission components and to the second pump through another transmission component of the transmission components; wherein the first pump is a pressure transmission pump that supplies a pressure transmission fluid to a pressure transmission target to drive the pressure transmission target; wherein the second pump is a lubrication pump that supplies a lubricating fluid to a lubrication target to lubricate the lubrication target; wherein the second pump is configured to be driven by any one of the first and second drive sources (E, M) even in case that the other one of the first and second drive sources (E, M) is stopped, wherein one of the first and second input shafts (S3, S4) is inserted into the other of the first and second input shafts (S3, S4) and rotatable about a rotational axis relative to the other of the first and second input shafts (S3, S4), and wherein the power unit (1, 101) further comprises different flow paths through which the lubricating fluid and the pressure transmission fluid respectively flow.