A file transfer method, applied to file transmission between a first device owned by a first user and a second device owned by a second user, the first device being wirelessly connected to the second device and the first device and the second device being wirelessly connected to a server, the first device comprising a file, a display unit, and an input unit electronically connected to the display unit, the method comprising: displaying the file and an image stored in the first device on the display unit of the first device when the image, comprising a face image of the second user, is opened; generating a command when the file is dragged to the face image of the second user shown in the image via the input unit and is then released; and transferring the file from the first device to the second device according to the command, characterized by: storing a plurality of photos comprising faces of different users into a database of the server as a comparison basis; capturing, when the file is dragged to the face image of the second user shown in the image and is then released, a released position on the image where the file is released and accordingly generating a first coordinate by using the first device; transferring the first coordinate and the image from the first device to the server; performing, after the first coordinate and the image are received by the server, a face detection in order to find out the position of the face image of the second user shown in the image, and generating a second coordinate reflecting said position; determining whether the first coordinate falls on the second coordinate; transmitting, if the first coordinate does not fall on the second coordinate, an error message to the first device through the server; performing, if the first coordinate falls on the second coordinate, a face recognition through the server in order to compare the face of the second user with the faces of different users of the plurality of photos stored in the database, and accordingly generating a response message; transmitting, by the server, the response message to the first device; transferring the file from the first device to the server according to the response message; and transferring the file from the server to the second device. displaying the file and an image stored in the first device on the display unit of the first device when the image, comprising a face image of the second user, is opened; generating a command when the file is dragged to the face image of the second user shown in the image via the input unit and is then released; and transferring the file from the first device to the second device according to the command, characterized by: storing a plurality of photos comprising faces of different users into a database of the server as a comparison basis; capturing, when the file is dragged to the face image of the second user shown in the image and is then released, a released position on the image where the file is released and accordingly generating a first coordinate by using the first device; transferring the first coordinate and the image from the first device to the server; performing, after the first coordinate and the image are received by the server, a face detection in order to find out the position of the face image of the second user shown in the image, and generating a second coordinate reflecting said position; determining whether the first coordinate falls on the second coordinate; transmitting, if the first coordinate does not fall on the second coordinate, an error message to the first device through the server; performing, if the first coordinate falls on the second coordinate, a face recognition through the server in order to compare the face of the second user with the faces of different users of the plurality of photos stored in the database, and accordingly generating a response message; transmitting, by the server, the response message to the first device; transferring the file from the first device to the server according to the response message; and transferring the file from the server to the second device. storing a plurality of photos comprising faces of different users into a database of the server as a comparison basis; capturing, when the file is dragged to the face image of the second user shown in the image and is then released, a released position on the image where the file is released and accordingly generating a first coordinate by using the first device; transferring the first coordinate and the image from the first device to the server; performing, after the first coordinate and the image are received by the server, a face detection in order to find out the position of the face image of the second user shown in the image, and generating a second coordinate reflecting said position; determining whether the first coordinate falls on the second coordinate; transmitting, if the first coordinate does not fall on the second coordinate, an error message to the first device through the server; performing, if the first coordinate falls on the second coordinate, a face recognition through the server in order to compare the face of the second user with the faces of different users of the plurality of photos stored in the database, and accordingly generating a response message; transmitting, by the server, the response message to the first device; transferring the file from the first device to the server according to the response message; and transferring the file from the server to the second device.