The invention discloses a replacing technology for a three-cross-three-track switch, which comprises the following steps: (1) surveying and setting out; (2) pre-laying the track switch and middle track panels, and pre-laying the track switch and the middle track panels to be replaced in a site to be pre-laid; (3) removing diamond crossing; (4) replacing the middle track panels at two sides of the diamond crossing; (5) removing the track switch integrally; (6) installing the track switch which is pre-laid and needing change ; (7) assembling the diamond crossing; and (8) recovering lines, wherein the steps have the key improvement that the step (1) comprises the following steps: taking two blunt angle frogs of the diamond crossing as reference for determining an axle wire, and taking the axle wire as reference for determining the positions of a head frog and an end frog for replacing the track switch. The invention has the advantages of adopting the axle control method for the construction of the track switch, controlling the position of the track switch according to the axle wire, reducing the surveying steps and improving the efficiency of construction.