The invention relates to the technical field of shaft mechanical tunneling and discloses a shaft mechanical tunneling construction method. The shaft mechanical tunneling construction method comprisesthe steps of construction preparation, working pit pre-digging, open caisson blade foot ring and vertical shaft locking opening manufacturing, auxiliary equipment installation, initial lifting and tunneling machine hoisting, open caisson wall lubricant grouting, tunneling excavation, slag discharging, open caisson sinking and heightening, open caisson bottom sealing drainage and open caisson wallrear lubricant replacement. The construction safety of the underground large-diameter shaft can be improved, and the construction efficiency and the mechanization degree are improved.