Image forming apparatus that automatically creates an index and a method thereof

An image forming apparatus capable of automatically creating an index, and a method for the same. The image forming apparatus includes a scan unit to scan a document, a text/image separation unit to separate the scanned document into a text area and an image area and to separate texts in the text area into symbols, an index determination unit to extract one or more properties of the separated symbols and to compare the extracted symbol properties with one or more index thresholds to determine whether text including the symbols is an index object, and an index page creation unit to create an index page including the text determined as the index object and information about a page including the text that corresponds to the index object. Accordingly, since the index page is automatically created, main contents of each page of the document can be easily selected and/or presented. Also, a search for desired contents in the document is facilitated by a link between the index page and original contents of the pages in the document, thereby improving user convenience.