In the process of writing and drawing with traditional pencils, everyone usually encounters various problems such as broken pen tip, thickened after use, eraser for writing mistakes, and poor hand holding at the end of writing. In view of the above actual problems, a pen sleeve integrating pencil sharpener, eraser and extender is designed. The total length is 50mm, small and light. The eraser is installed by plugging and unplugging, and can be replaced for permanent use in time. At ordinary times, it is only necessary to put it on a pencil and put it in a pencil case. At the same time, it also has the function of a pen holder, which can be clamped on writing paper, books and pockets. It is also convenient to carry out. In the future, I will not worry about the premature waste of broken tips or writing for a pencil sharpener, wrong mistakes for erasers, and poor holding of pens.