A screw nail correcting apparatus used for treating ingrown nails seen in human feet and/or hands adapts to different nail widths and to the changes that may occur in time on the same nail and practically enables pulling of the nail with an amount of force complying with the requirement. The fact that the apparatus is not a single piece and that it can be mounted separately from both sides of the nail provides ease of use, and the screw mobile part in the middle thereof helps to adjust the tautness according to the requirement of the nail at the concerned moment.