<；P>；PROBLEM TO BE SOLVED: To provide an opening and closing structure of a roof part for a plastic greenhouse, inexpensive and lightweight, and capable of surely closing an opening part even when a strong wind blows. <；P>；SOLUTION: This opening and closing structure of a roof part includes opening a skylight part 130 which is formed on a roof part 120 of a plastic greenhouse 100 through rolling a skylight sheet 201 with a rolling pipe 230, and while rewinding the skylight sheet 201 so as to cover and close the skylight part 130, and also rewinding the skylight sheet 201 until to drop off from the upper end surface of a pipe supporting body 240 set on the middle of the inclined surface of the roof part 120 to the inclined surface of the roof part 120, and rotating the rolling pipe 230 in a direction same as a rewinding direction. As a result of this, the skylight part 130 can be closed while keeping a tensioned condition of the skylight sheet 201 through moving and engaging while rolling the skylight sheet 201, with a pipe holding part 241 of a nearly U shape cross section, formed on the pipe supporting body 240. <；P>；COPYRIGHT: (C)2009,JPO&INPIT
