A roller unit includes a base bracket (2) that supports a slide door, a cable holder (11) formed integrally with the base bracket (2) and that holds cable ends (112a and 113a) of cables (112 and 113), and a cable guide (40) detachably installed at the cable holder (11) and that guides the cables (112 and 113), wherein the cable guide (40) is formed to separate the cables (112 and 113) from the base bracket (2), and a load applied to the cable guide (40) by tensile forces of the cables (112 and 113) is received by the cable holder (11) and the base bracket (2).