An image server and an image communication system capable of displaying images of plural image servers differing in IP address on a browser window by using a versatile browser, and a methods for controlling them. Plural image servers communicate with a client computer displaying image information presented from image servers through a network. Of the plural image servers, the controller of a certain image server receives a request from the client computer, and displays the image data of the image server and image data of other plural image servers simultaneously on the browser window of the client computer. Accordingly, the controller of the designated image server creates display information, and supplies the information to the client computer.