A drilling tool with improved structure to improve chips discharging performance. The drilling tool comprises a cutting insert 60 having a cutting edge 62 at the front end portion and a main body 10 mounted with the cutting insert 60, further, the drilling tool comprises a hollow discharge channel 12 formed inside the main body 10, and the discharge channel 12 has a curved surface 14 for guiding the chips S in a direction towards the base end portion opposite to the front end portion.