A method and apparatus for inputting and outputting data by using a virtualization technique are provided. The method includes generating a virtual operating system (OS) for the external device, which is connected to a host, based on OS information stored in the external device, setting a partial area of a storage of the host as virtual storage for the external device, and storing the data in the virtual storage or a memory of the external device in response to a request for inputting and outputting the data from the virtual OS.