To provide a system binder equipped with a movable type binder so as to facilitate writing on paper, in regard to the system binder for a system pocket notebook, a loose-leaf notebook or the like.

Slide surfaces are provided on the right and the left of the base part of the binder (2) so that the binder can move longitudinally along a groove of a structural part (1). Moreover, the structural part itself is made movable laterally on the upper and lower slide surfaces of the back cover, along a groove provided in the base part thereof.