1. Different functions Modem is a computer networking of a necessary equipment, with a modem computer to dial the Internet, and the router is a way to help multiple computers to share a network of equipment, with the help of a router, several computers can be in the same cable network, but the router is not the necessary computer Internet equipment, no routers, The computer can still be connected via modem.
2. Different connection methods，Due to the role of different, the two connection way also has a difference, one end of the modem connection telephone line, a connection computer or router, while the router connected to the modem, the other end can only connect the computer, directly with the router to connect the telephone line and the computer is unable to achieve networking.
3. Different shape，The shape of the modem is relatively single, like a flat rectangular box, very small, and the shape of the router is a variety of shapes, there are rectangular shape, there is an oval, the volume of the overall larger than the modem, and wireless routers with a number of different antenna devices.
4. Different ports The port shape and number of the two are not the same, the modem port generally only two, a connection telephone line, a connection network cable, and the router's mouth is more, usually there are five, one with the modem connection, the rest can be arbitrarily with one or more computers connected.