PURPOSE: To provide a slip control device of a lock-up clutch for a vehicle capable of realizing the slip control as much as possible.

CONSTITUTION: The region A where the judder of a lock-up clutch is easily generated and the region B where the judder is difficult to be generated are preliminarily stored in a region storing means 200, and a slip execution region control means 204 prohibits the slip control in the region A when the region in which the judder of a lock-up clutch 32 is judged by a judder judging means 198 is the region A, while permits the execution of the slip control only in the region B where the judder is difficult to be generated. Thus, even if the judder is generated, the slip is executed in the region B where the judder is difficult to be generated, and the effect of the slip control, i.e., the effect to improve the fuel consumption can be gained as much as possible.