Hydraulic dump tractor trailer is an agricultural vehicle that transports materials by tractor traction, also known as agricultural trailer, and is an important mechanized transportation method in agricultural production. Small wheeled or hand-held tractors pull small trailers for short distance or field transportation, meeting the needs of small-scale agricultural production and operation. Transporting grain, agricultural materials, etc. by towing trailers with large and medium-sized wheeled tractors can fully utilize the role of tractors and meet the needs of large-scale agricultural production and operation.