A control device of a work vehicle, the work vehicle including a drive source, a traveling device (240, 250) that is driven by a drive force of the drive source, a power transmission device of which an input shaft is connected to the drive source and an output shaft is connected to the traveling device (240, 250), the power transmission device transmitting the drive force which is input to the input shaft to the output shaft, and an operation device that is used to give an instruction for a magnitude of the drive force of the drive source, the control device comprising: a required output torque determination unit that determines a required output torque of the power transmission device based on an operation amount of the operation device and a traveling speed of the work vehicle; a traveling load estimation unit that estimates a traveling load torque related to a traveling load on the work vehicle; a required output torque correction unit that corrects the required output torque such that the required output torque is included in an allowable output torque range including an estimated traveling load torque; and a drive source control unit that outputs a control signal for the drive source based on a corrected required output torque; characterized in that the control device of the work vehicle further comprises: a work state specifying unit that specifies a work state of the work vehicle; and an allowable range determination unit that determines the allowable output torque range based on a specified work state; the work vehicle further includes work equipment, and in a case where the work state is an excavation state using the work equipment, the allowable range determination unit determines the allowable output torque range to be narrower than an allowable output torque range when the work state is a traveling state. a traveling device (240, 250) that is driven by a drive force of the drive source, a power transmission device of which an input shaft is connected to the drive source and an output shaft is connected to the traveling device (240, 250), the power transmission device transmitting the drive force which is input to the input shaft to the output shaft, and an operation device that is used to give an instruction for a magnitude of the drive force of the drive source, the control device comprising: a required output torque determination unit that determines a required output torque of the power transmission device based on an operation amount of the operation device and a traveling speed of the work vehicle; a traveling load estimation unit that estimates a traveling load torque related to a traveling load on the work vehicle; a required output torque correction unit that corrects the required output torque such that the required output torque is included in an allowable output torque range including an estimated traveling load torque; and a drive source control unit that outputs a control signal for the drive source based on a corrected required output torque; characterized in that the control device of the work vehicle further comprises: a work state specifying unit that specifies a work state of the work vehicle; and an allowable range determination unit that determines the allowable output torque range based on a specified work state; the work vehicle further includes work equipment, and in a case where the work state is an excavation state using the work equipment, the allowable range determination unit determines the allowable output torque range to be narrower than an allowable output torque range when the work state is a traveling state. a required output torque determination unit that determines a required output torque of the power transmission device based on an operation amount of the operation device and a traveling speed of the work vehicle; a traveling load estimation unit that estimates a traveling load torque related to a traveling load on the work vehicle; a required output torque correction unit that corrects the required output torque such that the required output torque is included in an allowable output torque range including an estimated traveling load torque; and a drive source control unit that outputs a control signal for the drive source based on a corrected required output torque; characterized in that the control device of the work vehicle further comprises: a work state specifying unit that specifies a work state of the work vehicle; and an allowable range determination unit that determines the allowable output torque range based on a specified work state; the work vehicle further includes work equipment, and in a case where the work state is an excavation state using the work equipment, the allowable range determination unit determines the allowable output torque range to be narrower than an allowable output torque range when the work state is a traveling state. a work state specifying unit that specifies a work state of the work vehicle; and an allowable range determination unit that determines the allowable output torque range based on a specified work state; the work vehicle further includes work equipment, and in a case where the work state is an excavation state using the work equipment, the allowable range determination unit determines the allowable output torque range to be narrower than an allowable output torque range when the work state is a traveling state.