A multi-orientation adjustable clamp device comprises a stationary and a movable clamp, wherein a stationary connector disposed on a top end of the stationary clamp is pivotally jointed with a locking block by a linking stud, and a fixing hole is formed at one end of the linking stud for fixing a linking lever. The structure of the clamp device is characterized in: disposing a crank between the stationary clamp and the locking block; and, a first and a second connector arranged at two ends of the crank respectively for coupling with the stationary connector and the locking block individually to form two pivot-joint devices to offer a multi-orientation adjustable function to this invention.