The present invention relates to a line winch (1) and to a method to pull in and let out line. Line winch (1) has a rotatably mounted winch drum (2). Line (3) is wound up by means of a driving device, for example a crank (V) or a motor, by means of which the winch drum (2) can be rotated at different speed in a first direction in order to pull in the line (3), and in a second direction in order to let out line (3). Line (3) under load is pulled in on to the winch drum (2) in that a force or a torque is directed via a driving shaft (5) from the driving device in a first direction, whereby a to the driving shaft connected cone coupling (27, 29) provided with an internal trapezoid thread (16) is tightened, so that a gear wheel (33) mounted on a shaft (32) is actuated, and by meshing with a gear wheel (35), which is mounted on a shaft (A), rotates said wheel, so that the winch drum (2) is operated in a first direction directly or indirectly by means of the gear wheel (35) and another gear wheel (39), which is placed on the shaft (A), by means of a free wheel (35a) acting between the gear wheels (35, 39). Loaded line (3) is let out in that the driving device is actuated in a second driving direction, whereby the cone coupling (27, 29) 'is released and allows that line is let out until the load of the line again tightens the cone' coupling by means of the trapezoid thread when actuation of the driving device in the second driving direction is terminated.