A mini-invasive device for endourologic treatment includes a tubular conduit, longitudinally flexible, configured to be inserted through and along the operating channel of an endoscope. The tubular conduit internally defines an essentially non-deformable lumen, has a proximal portion having a connector to a suction device, has a distal portion intended to project from the distal tip of the endoscope, and internally delimits a suction conduit, within which at least one tool can be removably inserted to be used in endourologic treatment.