A monopolar electrosurgical instrument comprising a cylindrical metallic electrode which is connected to one pole of a radio frequency generator on one extreme; said electrode comprising a liquid supply for cooling, a handle 7 that covers part of the electrode, a part 6 covered with an insulative material, and a coagulating and cutting uninsulated tip; said tip comprising a round ending part 2, a part 3 attached to a cutting metal blade 5 near the end, and a part 4 non-attached to a cutting metal blade. It is useful for precisely cut the tissue that it is previously coagulated, using a single instrument, and avoiding risk of bleeding.