Handling device for handling drill string components (8,8',8") in a rock drilling rig, including a rotator device, which is arranged for rotation and driving a drill string and is moveable to and fro, supported by a feed beam, wherein the handling device includes a gripper unit for gripping drill string components (8,8',8") that are to be put into and be brought out from an active drill string position of the rock drilling rig, and wherein the gripper unit includes grippers (12,13,14) operational for gripping components positioned in a gripping position, which defines a grip position axis, characterized in - that the gripper unit is supported swingable between: a) a first position, wherein the gripper unit is positioned for engagement with an end portion of a first drill string component and an end portion of a second drill string component (8") in and aligned with said active drill string position, and b) a second position, wherein a gripper unit is positioned for engagement with an end portion of a drill string component in a delivering position for drill string components that are to be brought into respectively taken away from said active drill string position, wherein the gripper unit includes rotation means, for rotating, in said first as well as said second position, at least one of the components from the group: a second drill string component (8"), a lifting plug, a flush water swivel - for screwing together and screwing apart this component with and from a gripped first drill string component, wherein the rotation means are comprised of a rotation grip unit for simultaneous gripping and rotating any one of: said end portion of the second drill string component, said lifting plug, said flush water swivel, and wherein the gripper unit is provided with a first set of grippers for gripping said end portion of the first drill string component and a second set of grippers for allowing gripping, together with the rotation grip unit, of any one of: said end portion of the second drill string component, said lifting plug, said flush water swivel. - that the gripper unit is supported swingable between: a) a first position, wherein the gripper unit is positioned for engagement with an end portion of a first drill string component and an end portion of a second drill string component (8") in and aligned with said active drill string position, and b) a second position, wherein a gripper unit is positioned for engagement with an end portion of a drill string component in a delivering position for drill string components that are to be brought into respectively taken away from said active drill string position, a) a first position, wherein the gripper unit is positioned for engagement with an end portion of a first drill string component and an end portion of a second drill string component (8") in and aligned with said active drill string position, and b) a second position, wherein a gripper unit is positioned for engagement with an end portion of a drill string component in a delivering position for drill string components that are to be brought into respectively taken away from said active drill string position, said end portion of the second drill string component, said lifting plug, said flush water swivel, and wherein the gripper unit is provided with a first set of grippers for gripping said end portion of the first drill string component and a second set of grippers for allowing gripping, together with the rotation grip unit, of any one of: said end portion of the second drill string component, said lifting plug, said flush water swivel.