The invention discloses a method for manufacturing and mounting a 120-meter long roof tile at high altitude, which is characterized by comprising the following steps of: (A) mounting a high-altitude movable platform: (a) paving roadbed square stones and sleepers, and mounting a rail; (b) mounting a tower base and wheels; (c) mounting tower balance weight; (d) mounting a moulding press supporting frame, a platform, a guy rope and a top supporting frame; and (e) mounting a tile press; and (B) mounting the roof tile: (a) providing a base plate; (b) pressing the base plate by using the tile press, and conveying the roof tile, namely raising on one side of the front part of a pressing roller way of the tile press according to the roof pitch, pressing the roof tile along the roof, conveying theroof tile, and conveying mould tiles by using a plurality of sliding supports; and (c) beating self-tapping self-drilling nails to fix the roof tile. The method for manufacturing and mounting the 120-meter long roof tile at high altitude has the characteristics of reducing machinery cost and labor cost, preventing the roof tile from being damaged in the conveying process, guaranteeing the safety of high-altitude operators, along with short construction period and high mounting quality.