It is a mobile Wi-Fi router of 3G all-in-one design that can easily connect Wi-Fi as for hardware. Mobile Wi-Fi router of 3G all-in-one design that can be used as access point by converting electric wave for cellular phone into Wi-Fi even in place in which access point of Wi-Fi doesn’t exist in the place where it is in 3G area. The notebook computer and the equipment for Wi-Fi such as portable game machines can be connected with the Internet only by turning on the power supply of the main body. The size of the main body can be carrying to light-hearted because of the small size and about 80g and lightness. Moreover, because the connections simultaneously up to five are possible, it can readily enjoy the online fighting type game etc. by the companion even in the destination.