VEHICLE

A hybrid work vehicle is capable of smooth work travel using a work device with a low output internal combustion engine, while avoiding battery exhaustion. An internal combustion engine (E) that supplies drive power to a travel device (2) and a work device (9) via power transmission means (1), a motor generator (4) that is driven by a battery (B), a load information generation part (51) that generates load information representing a sudden increase in rotational load, an assist characteristic determination part (52) that determines motor assist characteristics defining an assist amount and an assist time period of assist control based on load information, and a motor control unit (7) that controls the motor generator (4) based on the motor assist characteristics are provided.