Abstract: The holdable multi-functional rotary device comprises a casing suitable to be held by users. The interior thereof is formed with a receiving space for arranging a driving unit and a battery. The driving unit has a motor and a driving shaft extending out of the casing. The power of the motor and driving shaft is transferred by speed change gear set. By changing speed change gear set, the rotary speed of the driving shaft is changeable. A plurality of rotary pieces are arranged around the driving shaft. The rotary pieces are capable to achieving predetermined effects with the rotation of the driving shaft. Thereby, the whole rotary device can be combined with rotary pieces and the rotary speed of the rotary pieces are adjustable. The rotary pieces can be attached to a fan, a massage device, a dust absorbing mask, a shoe brush, a golf rod brush, etc.