A method and apparatus for solving UI style conflicts in web application composition. The method includes the steps of: detecting, in the runtime environment of a web browser, a page element referring to duplicate UI style definitions in a web composite page; determining the UI style definition referred to by the page element in an imported widget or a local page from which it originates; and relating the page element and the determined corresponding UI style definition in the web composite page, so as to solve the UI style conflict.