The invention relates to an automatic adhesive cutting device. The device comprises adhesive tape reels, a feeding device, an adhesive cutting mechanism, a hot press and an adhesive-clamping pneumatic gripper 8 which are arranged in sequence, wherein the adhesive tape reels include an upper tape reel and a lower tape reel. The adhesive tape has a moving end. A finger press cylinder 2 is arranged at the front end of the feeding device. The moving end is fixed to the finger press cylinder 2, so that the adhesive tape is fixed. The feeding device can horizontally move to the adhesive-clamping pneumatic gripper 8 and fixing the adhesive tape to the adhesive-clamping pneumatic gripper 8. The adhesive cutting mechanism comprises an adhesive cutting cylinder 4, a bracket and a blade 5. The adhesive cutting cylinder 4 is installed on the bracket, and is specifically located at the end part of the feeding device. The adhesive cutting cylinder 4 is linked with the blade 5 to cut the adhesive tape. The automatic adhesive cutting device of the invention can fast and effectively cut upper and lower adhesive blocks and solves the problem that the cut ends of the adhesive blocks are bonded together, so that the operation continuity of an automatic tab machine and the stability of product quality are ensured, and the production efficiency is improved.