To provide a base pattern former by which the sliding face of a snow board or ski can be maintained good, the base pattern can be easily changed, and a base pattern can be formed at a required time and place.

Groove patterns 25A (25B, 25C) are formed on rollers 20A (20B, 20C) of this former. The rollers are rotatably supported by roller supporting parts 21A, 21B, 21C, 21D. Rollers 20A (20B, 20C) are heated by a heater 110 up to a prescribed temperature. Then rollers 20A (20B, 20C) are pressed against the sliding face of a ski board (snow board) 200 widening the gap between bearings 30A, 30B by operating a movable shaft 30. When the bearings 30A, 30B clamped the ski board (snow board) 200 from the width direction by contracting force of springs 33A, 33B, the former is rolled over the sliding face of the ski board (snow board) 200 by holding the handles 50A, 50B.