A fixing device for clamping a tissue comprises a support mechanism comprising a fixed connecting assembly and a drive assembly, and a clamp mechanism comprising closure members and capture portions, wherein each closure member comprises a closure connecting portion and a closure clamping portion in cooperation with one of the capture portions to clamp the tissue; wherein each closure connecting portion is provided with guide slots comprising a first slot portion and a second slot portion in communication therewith and has a relatively smaller radian, the fixed connecting assembly is provided with pins at least partially located in the guide slots, respectively, and the pins are slidable relative to the guide slots when the drive assembly moves relative to the fixed connecting assembly, so as to drive the closure clamping portions to move towards or away from each other. A system comprising the fixing device, and a method are provided.