A work vehicle comprising: an engine; a work implement; a travel device driven by the engine; a power transmission device that transmits driving power from the engine to the travel device; and a control unit for controlling the power transmission device; wherein, the power transmission device has: an input shaft; an output shaft; a gear mechanism that has a planetary gear mechanism (68, 69) and that transmits rotation of the input shaft to the output shaft; and an electric motor (MG1, MG2) connected to rotating elements of the planetary gear mechanism (68, 69); and the power transmission device is configured to change a rotation speed ratio of the output shaft with respect to the input shaft by changing a rotation speed of the electric motor (MG1, MG2); and the control unit has: a target torque determination unit that determines a target torque of the electric motor (MG1, MG2); wherein the power transmission device further has a mode-switching mechanism for selectively switching a transmission path of driving power in the power transmission device between a plurality of modes including a first mode and a second mode; characterized in that the work vehicle further comprises a hydraulic pump driven by the engine; wherein the work implement is driven by hydraulic fluid discharged from the hydraulic pump; and the control unit further has a target torque correcting unit that corrects the target torque with a correction torque; wherein, when the transmission path is in the first mode, the target torque correcting unit corrects the target torque with the correction torque being based on a first moment of inertia, the first moment of inertia including a moment of inertia of a rotor of the electric motor (MG1, MG2) and a moment of inertia of the rotating elements connected to the electric motor (MG1, MG2) and included in the transmission path of the first mode; and when the transmission path is in the second mode, the target torque correcting unit corrects the target torque with the correction torque being based on a second moment of inertia, the second moment of inertia includuing the moment of inertia of the rotor of the electric motor (MG1, MG2) and a moment of inertia of the rotating elements connected to the electric motor (MG1, MG2) and included in the transmission path of the second mode. an engine; a work implement; a travel device driven by the engine; a power transmission device that transmits driving power from the engine to the travel device; and a control unit for controlling the power transmission device; wherein, the power transmission device has: an input shaft; an output shaft; a gear mechanism that has a planetary gear mechanism (68, 69) and that transmits rotation of the input shaft to the output shaft; and an electric motor (MG1, MG2) connected to rotating elements of the planetary gear mechanism (68, 69); and an input shaft; an output shaft; a gear mechanism that has a planetary gear mechanism (68, 69) and that transmits rotation of the input shaft to the output shaft; and an electric motor (MG1, MG2) connected to rotating elements of the planetary gear mechanism (68, 69); and the power transmission device is configured to change a rotation speed ratio of the output shaft with respect to the input shaft by changing a rotation speed of the electric motor (MG1, MG2); and the control unit has: a target torque determination unit that determines a target torque of the electric motor (MG1, MG2); wherein the power transmission device further has a mode-switching mechanism for selectively switching a transmission path of driving power in the power transmission device between a plurality of modes including a first mode and a second mode; characterized in that the work vehicle further comprises a hydraulic pump driven by the engine; wherein the work implement is driven by hydraulic fluid discharged from the hydraulic pump; and the control unit further has a target torque correcting unit that corrects the target torque with a correction torque; a target torque determination unit that determines a target torque of the electric motor (MG1, MG2); wherein the power transmission device further has a mode-switching mechanism for selectively switching a transmission path of driving power in the power transmission device between a plurality of modes including a first mode and a second mode; characterized in that the work vehicle further comprises a hydraulic pump driven by the engine; wherein the work implement is driven by hydraulic fluid discharged from the hydraulic pump; and the control unit further has a target torque correcting unit that corrects the target torque with a correction torque; wherein, when the transmission path is in the first mode, the target torque correcting unit corrects the target torque with the correction torque being based on a first moment of inertia, the first moment of inertia including a moment of inertia of a rotor of the electric motor (MG1, MG2) and a moment of inertia of the rotating elements connected to the electric motor (MG1, MG2) and included in the transmission path of the first mode; and when the transmission path is in the second mode, the target torque correcting unit corrects the target torque with the correction torque being based on a second moment of inertia, the second moment of inertia includuing the moment of inertia of the rotor of the electric motor (MG1, MG2) and a moment of inertia of the rotating elements connected to the electric motor (MG1, MG2) and included in the transmission path of the second mode.