Auxiliary frame cross member and vehicle

The utility model discloses an auxiliary frame cross beam and a vehicle, at least three first arc-shaped sections are formed on the upper side of the auxiliary frame cross beam, the at least three first arc-shaped sections are sequentially connected in the left-right direction, the first arc-shaped section located in the middle is of an arch-shaped protruding structure in the up-down direction, and the first arc-shaped section located in the middle is of an arch-shaped protruding structure in the up-down direction. The first arc-shaped sections located at the two ends are of an arch-shaped pit structure, a second arc-shaped section is formed on the lower side of the auxiliary frame cross beam, and in the vertical direction, the second arc-shaped section is of an arch-shaped protruding structure in the direction from the left end and the right end of the auxiliary frame cross beam to the middle of the auxiliary frame cross beam. Through the shape and structure design of the auxiliary frame cross beam, the stre