The utility model provides a powder and particle material transportation semitrailer and a frame thereof. The frame comprises two longitudinal beams and a traction device installed between the two longitudinal beams and close to the front ends of the two longitudinal beams, wherein each longitudinal beam comprises an upper wing plate, a lower wing plate and a web plate connected between the upper wing plate and the lower wing plate. The positions close to the front ends of the web plates downwards protrude and extend to form protrusions, the positions corresponding to the protrusions, of the lower wing plates, are concave downwards to form concave portions for accommodating the protrusions. The traction device is installed at the concave portion positions of the lower wing plates of the frame, accordingly the frame and the traction device are designed to be integrated, the frame is simple in structure and convenient to manufacture, welding amount is decreased, and the whole powder and particle material transportation semitrailer can be light in weight. In addition, the strength for welding the frame and the traction device can well meet the strength design requirement of a product, and accordingly welding defects are not easily produced.