PURPOSE: To greatly increase the conveying capacity of a trough-type belt conveyor, by providing side rollers at the sending part of the endless belt of the conveyor so that the rollers have a prescribed inclination angle and can be titled forward and backward.

CONSTITUTION: At the straightly moving portion of a belt 3, the axes of right and left rollers 2 are kept parallel with the cross section of the belt. At the other portion of the belt 3 moving in the direction of an arrow (y), the lower parts of other side rollers 2 are displaced about pins 7 as fulcra oppositely to said direction at the inner part of the belt, namely, the upper parts of the side rollers are displaced about the pins in said direction at the outer part of the belt. The parts of the side rollers 2 displaced oppositely to the direction of the arrow (y) prevent the inner part of the belt 3 from moving up and prevent the outer part of the belt from moving down. The angle between the cross section of the belt 3 and the axis of each of the inclined right and left side rollers 2 is about 60 to 80°.