The present invention discloses a biomimetic bag opening device for an automatic filling line, comprising brackets left and right symmetrically arranged on the filling line for filling bags, the symmetrically arranged brackets moving in a horizontal relative motion respectively driven by a pull rod, a push bag plate facing the filling bag provided at a front end of the bracket, a row of gripper holes provided on the push bag plate in the upper and lower of the horizontal level respectively, two rows of grippers provided on the brackets behind the push bag plate and corresponding to the two rows of gripper holes, a gripper drive device driving two rows of grippers open or closed, and grasping fingertips of the grippers projecting or retracting from two rows of the upper and lower of the gripper holes. The present invention solves the problem that woven bags are automatically opened in a full-automatic weighing and packaging device, which can be used for the production of the non-lamination woven bag, semi-lamination woven bag and full-lamination woven bag. The grippers of present invention imitate the human fingers to grip woven bags and separate the bag mouth, the bag mouth can also be closed to prepare for next process after bagging completed, and structure installation and adjustment are convenient.