The invention discloses a long and thin type dovetail air rudder leading edge forming method. The method comprises the steps that a blank structure for a leading edge workpiece during die pressing is determined; the forming direction of a leading edge blank is determined; the leading edge blank is formed in a die pressing manner; the front end face and the rear end face of the aerodynamics windward face of the leading edge blank are milled to form inclined faces, and the assembling face is milled; and the leading edge blank is repaired and detected. By the adoption of the scheme of forming the windward face with the net size and forming the assembling face with the approximate net size, the ablation resisting ability of the windward face of the leading edge workpiece is improved. Meanwhile, it is ensured that a little allowance is reserved on the assembling face for follow-up repairing to meet the assembly requirement. The invention further discloses a forming die pressing die adopting a combined sectioning structure. High forming precision of the leading edge workpiece is ensured, and trimmings of the leading edge workpiece are reduced. Meanwhile, it can be ensured that the leading edge workpiece can be released from the die smoothly. Finally, the invention further discloses a special detecting tool carrying out repairing while carrying out detecting, the detecting efficiency of the leading edge blank is improved, and interchangeability of leading edge assembly is ensured.