The invention relates to an emergency tripping device of a reactor control rod assembly. The emergency tripping device is used for pulling up the head of a drive rod to separate the drive rod from a trip of a control rod assembly, wherein the head of the drive rod is provided with a concave groove. The emergency tripping device comprises an inner cylinder, upper hooks, an upper sleeve and a pull bar, wherein the inner cylinder is arranged right in the middle, the pull bar which is driven by the inner cylinder to move up and down is connected with the inner cylinder and arranged below the inner cylinder, the two sides of the pull bar are respectively provided with the upper hooks; the central portions of the upper hooks are connected with the upper sleeve though a revolving shaft and move up and down with the upper sleeve; the upper portion, middle portion and lower portion of the same side which belongs to the upper hooks and is close to the tail end of the pull rod are respectively provided with an upper embossment, a middle embossment, and a lower embossment, the tail end of the pull rod is arranged at a position where the pull rod can poke at the middle embossment and the upper embossment, and the lower embossment is matched with the groove of the head of the drive rod and is embedded in the drive rod. When the control rod assembly is pulled out by accident, the emergency tripping device is adopted, by using the pull rod to clamp the drive rod and pulling up, the tripping operation between the control rod assembly and the drive rod is completed.