To enhance the efficiency of excavation work by omitting time for reciprocation from an excavating place of a bucket to a ground side.

This excavation method includes a process for making a cutting edge (27) of the bucket (10) (e.g. a clamshell bucket: the excavation method can be applied to the general buckets with the function of excavation) in an opened state bite into soil to be excavated, a process for housing the soil in the bucket (10) by closing the bucket (10), a process for crushing or chopping the soil housed in the bucket (10), and a process for discharging the crushed or chopped soil to the ground side via a discharge line (mud lifting pipe) (12).