Disclosed is a method for constructing a lexical tree for speech recognition, wherein, even though a name included in an address book in a communication device such as a cellular phone and a word such as “house/office/cellular phone” are sequentially and successively uttered, the method allows the uttered speech to be precisely recognized. The method for constructing a lexical tree constructs a lexical tree including a name tree composed of names included in an address book in a communication device and an expansion vocabulary tree composed of words following the names, respectively.