The invention discloses a hydraulic support base overall boring and alignment method. The hydraulic support base overall boring and alignment method comprises the steps that (1), before a base and outer main reinforcements on two sides of the base are spliced and welded, one process hole is firstly machined in each outer main reinforcement taking the bottom surface and the front end surface of thecorresponding main reinforcement as the datum correspondingly; (2), the two outer main reinforcements are spliced and welded to two sides of the base according to the design requirements, and an overall base is fabricated; (3), after two pad blocks are alternately placed on a double-surface boring machine workbench, the overall base is inverted on the two pad blocks; (4), alignment is performed on the overall base, fastening bolts at the front ends of boring rods on two sides of a double-surface boring machine are made to be both capable of stretching into the corresponding process holes in the overall base, a boring cutter is installed and a double-surface boring machine coordinate system is adjusted, two pre-boring holes to be machined are observed, the fact that the two pre-boring holes to be machined are adjusted to both have machining allowance is deemed as the fact that alignment is performed, and then boring machining operations performed on the two pre-boring holes to be machined can be started. By means of the hydraulic support base overall boring and alignment method, the problem of the boring height being insufficient is solved, tediousness of performing alignment operations according to marked lines is omitted, and the production efficiency is substantially improved by 30% or above.