A method and a device for determining a display mode of an electronic document on a screen are provided. The method may comprise: obtaining the size of the screen and the original layout size of the electronic document; determining, from the obtained original layout size, a document layout length in a layout direction of the original layout of the electronic document; determining, from the obtained size of the screen, a screen reading length in a reading direction of the screen; and comparing the document layout length with the screen reading length to determine whether a fixed-layout display mode or a flow display mode shall be selected to display the electronic document.