The invention discloses a method for mounting crawler cranes in side slope sites. The method includes steps of S1, preparing for construction, to be more specific, a,
marking out appropriate lifting platforms for
truck cranes, treating foundations and leveling the sites; b, selecting the appropriate
truck cranes; c, transporting main units, crawlers, counterweights and main arms of the crawler cranes to main unit position platforms and assembling the main units, the crawlers, the counterweights and the main arms; d; respectively driving every two corresponding
truck cranes to the corresponding lifting platforms and transporting
tower arms onto the lifting platforms; e, respectively computing the stretching length required by each lifting arm of each truck crane, assembling the
tower arms besides the lower-end lifting platforms and determining a lifting point for lifting each truck crane on the corresponding
tower arm according to the position of the
gravity center of each section of each lifting arm in the corresponding tower arm; S2, simultaneously lifting each tower arm by the aid of the two corresponding truck cranes; S3, grouping each tower arm and the corresponding main arm in the air by the aid of the two corresponding truck cranes; S4, operating the lifting arms of the truck cranes and taking off lifting hooks. The method for mounting the crawler cranes in the side slope sites has the advantages of speedy mounting and high efficiency.