This study focuses on the development of a force sensing mechanism for surgical scissors. Previous studies have suggested using a logarithmic spiral curve shape scissors. However, this method can be applied only to blades with logarithmic vortex curves. This study proposes a new mechanism that can be used with straight scissors. The proposed mechanism consists of a linear slider and a cam follower of the same shape as a scissors blade, enabling a constant cutting force. The experimental results indicate that the proposed mechanism enable constant cutting force irrelevant to cutting speed or scissor shape.