Abstract: The present invention discloses a method for query of domain names of telephone numbers, e.g., E.164 numbers. The method comprises: in ENUM DNS (Electronic numbers to URI Mapping Domain Name System), dividing a domain name of a telephone number into a public domain name part and a digit domain name part; storing sequentially public domain name information separated by spacer(s) in the public domain name part and the data obtained by arranging digits in the digit domain name part in a preset order into nodes of a search tree according to storage rules of the search tree; on receiving a query request, the ENUM DNS obtaining the public domain name information of the domain name and finding the corresponding nodes according to search tree rules; obtaining the digits separated by spacer(s) in the domain name, arranging the digits into data in a prescribed order of the system, and finding the next-level nodes of the search tree.