The utility model provides a digging shovel for a bar pit. The digging shovel comprises a shovel body, wherein the shovel body comprises a left shovel body and a right shovel body; each of the left shovel body and the right shovel body comprises a shovel shaft, a connecting piece and a shovel head; the two connecting pieces are arranged in a cross manner and are mutually hinged; the two shovel heads are arc shovel heads and are respectively connected with the lower ends of the two connecting pieces through threads, so that the shovel heads with different sizes can be changed according to the bar pits with different sizes; the two shovel shafts are respectively connected with the upper ends of the two connecting pieces in a moving manner; each of the two shovel shafts comprises multiple sections of secondary shovel shafts; every two adjacent sections of secondary shovel shafts are in threaded connection; the quantity of the secondary shovel shafts can be increased or reduced according to the requirement, so that the shovel shafts adapt to the bar pits with different depths; a taper drift is connected to the end part of the section of the secondary shovel shaft positioned at the rearmost end through threads; if a harder soil layer is found in the digging process, soil can be broken through the taper drift, so that assisting tools required during the digging process are reduced.