Operating scalpel with shell

The invention relates to an operating scalpel with a shell. The operating scalpel is characterized by comprising a scalpel handle (1) and a scalpel point (2); the scalpel handle (1) and the scalpel point (2) are replaceable, and the scalpel shell (3) is positioned on the scalpel handle (1) and can be extended and retracted along the scalpel handle (1). The operating scalpel has the advantages that the operating scalpel is provided with the scalpel shell capable of protecting the scalpel point, and accordingly the operating scalpel can be prevented from mistakenly injuring medical staffs after being opened; the operating scalpel further has a locking function, secondary use of the operating scalpel can be prevented, and accordingly hidden sanitary trouble can be completely prohibited.