The present invention relates to an external shading apparatus for a greenhouse comprising: a shading mesh, which is moved forwards and backwards on the outside of the greenhouse, wherein an upper guide string, joined to the center of a front end portion, passes over an upper portion of the outside of the greenhouse and is wound around a front winding roller installed on the outside of the front side of the greenhouse, is installed, and left and right-side guide strings, connected to a left side and a right side, respectively, pass over left and right sides of the outside of the greenhouse and are wound around the front winding roller, and a rear side is installed to be wound around a rear winding roller installed on the outside of a rear side of the greenhouse an upper guide unit which has an upper pulley joined and installed on the outside of an upper portion of a frame located on the front end portion of the greenhouse and guides the upper guide string of the shading mesh and a plurality of left and right-side guide bodies which are joined and installed on the outsides of lower portions of the left and right-sides of the frame of the greenhouse. The left and right-side guide bodies are in the shape of a housing having an open front and rear sides and an open upper portion, has left and right-side guide strings of the shading mesh which penetrate the inside in forward and backward directions, and comprise a lateral side guide unit which enables both lateral sides of the shading mesh to pass forwards and backwards between left and right-side guide rollers.COPYRIGHT KIPO 2017본 발명은 전방끝부분 가운데부분에 연결된 상부가이드끈이 비닐하우스의 외측면 상부를 지나 비닐하우스의 전방 외측에 설치된 전방권취롤러에 권취되게 설치되고 좌우양측에 각각 연결된 좌우측 측면가이드끈은 비닐하우스의 외측면 좌우양측을 지나 전방권취롤러에 함께 권취되게 설치되며 후방은 비닐하우스의 후방 외측에 설치된 후방권취롤러에 권취되게 설치되어 비닐하우스의 외측에서 전후로 이동되면서 전방으로 펼쳐지거나 후방으로 권취되는 차광망과, 비닐하우스의 전방끝부분에 위치된 골조프레임의 상부 외측에 연결설치되는 상부도르래가 구비되어 차광망의 상부가이드끈을 가이드하는 상부가이드부와, 비닐하우스의 골조프레임 좌우양측 하부 외측에 연결설치되는 다수개의 좌우측 측면가이드몸체가 구비되고 좌우측 측면가이드몸체는 전후방 및 상부가 개
