To provide a roller support device capable of enhancing the operating efficiency of roller mounting/removal.

This roller support device is structured as follows: A kneading roller 16 is rotatably pivoted by the bearing part 12 of a roller holder 11 supported in a freely rotating manner inside an inner frame 10. The axis G1 of the roller holder 11 and the axis G2 of the kneading roller 16 are eccentrically arranged by a gap "d1". The roller holder 11 is rotated by a lever 21, and the lever 21 is urged by the resilient force of a compression coil spring 28 through a rod 23. Further, the compression coil spring 28 loses its resilient force by turning a thumb nut 30 so as to cause the receding of a moving piece 25, and thereby, the kneading roller 16 can break away from a swinging roller. The lever 11 and the compression coil spring 28 are arranged outside of the inner frame 10.