To provide a biological tissue closing device capable of closing an injury hole formed in a biological tissue membrane easily and securely.

The biological tissue closing device 1 is provided for closing the injury hole penetrating the biological tissue membrane. The biological tissue closing device comprises a main body 2 whose tip is inserted into the biological tissue through the injury hole and a closing means 56 installed attachably and detachably on the tip of the main body 2. The closing means is inserted into the biological tissue with the tip of the main body 2 and is pressed onto the inner surface of the biological tissue for closing the injury hole. The closing means 56 is inserted into the biological tissue by operating the main body 2, pressed and fixed onto the inner surface of the biological tissue by an anchoring means 48 and closes the injury hole.