The invention provides a surgical instrument warning system and method and a control system. The warning system comprises a scalpel, a power control system, a warning device and a protective shell. The power control system outputs power according to a control instruction sent by an external terminal and moves in a reciprocating mode according to the output power so as to drive the scalpel to move to the bottom of the protective shell in a reciprocating mode in the protective shell. The warning device is arranged on the inner wall of the protective shell and used for monitoring touch information of the power control system, whether a target distance between the scalpel and the bottom of the protective shell is not larger than a limit value or not is determined according to the touch information, first warning information is generated when the target distance is not larger than the limit value, and the first warning information is sent to the external terminal. According to the scheme, operating safety can be improved.