The invention relates to the technical field of tunnels and underground projects, in particular to an excavation method of a tunnel shaft. By drilling a plurality of holes of smaller diameters at themoment, the underground water condition, the adverse geology condition and the like can be pre-judged, the matching degree of geological exploration data can be verified conveniently, so that guidancecan be provided for follow-up construction, and the construction risk and difficulty are lowered; and meanwhile, excavation is conducted from the upper side to the lower side, the limitation of forming a main tunnel at the bottom of the shaft is not needed, the non-explosion type construction manner can be adopted, and therefore the safety is high; rock and soil can be drilled loose in advance,the construction efficiency of excavation is improved, the work period is shortened, especially the operation time of an artificial deep foundation pit is shortened, the safety risk is effectively lowered, and construction cost is saved; and the excavation method of the tunnel shaft has broad popularization significance.