To provide a sheet folding machine constructed to permit easy setting of an space between folding rollers.

This sheet folding machine has a display part, in which a folding roller consisting of (a) through (g) touch keys 2, a movable roller for which a vertical or horizontal arrow is marked and 8 (+) marked fixed roller, a buckle 8 for which 1 through 6 numbers are marked, a folding knife 9 and the like are displayed on a display screen 1. Touching a folding form (a) gives various folding form displays on the display screen 1. A preset folding form out of these is selected, and then the maximum and minimum values for sheets passing between folding rollers are computed by a control part and the values are displayed on a sheet number display column 3 on the basis of the use of the next buckle or not. A space between the folding rollers can be adjusted in accordance with the number of the sheets displayed thereon.