The present invention employs a mosquito net to make the mosquito prevention window for preventing mosquitoes, insects and all large dusts to be referred as a mosquito prevention window. In order to open the door and the window to increase light and enhance ventilation, the mosquito prevention device is mounted on a window (car window or house window). The device may achieve the maximum effectiveness using a pulling apparatus, an arbitrary positioning apparatus and a fastening apparatus, which may utilize the zipper, snaps, buttons or ropes to be fixed at a location and for sealing.用防蚊帳做成防蚊窗,可防止蚊蠅和所有大型灰塵,叫做防蚊窗。因為門窗打開光線增加透風度增加,把防蚊裝置設在窗子(車窗或房子門窗)上,這裝置可因拉動式裝置、隨意定點式裝置、固定式裝置產生<也可用器具拉縺.合扣.扣子.繩子:一邊固定於固定處使其可使器具密合>最大效用。防蚊裝置<也可用器具拉縺.合扣.扣子.繩子.橫拉式裝置:一邊固定於固定處使其可使器具密合>一防止蚊蠅和所有大型灰塵。拉動式裝置一可使產品有效式移動裝置。隨意定點式裝置一移動當中可隨點任意定點的裝置。固定式裝置一產品可固定於任何物體的裝置。用戶一使用者。