The invention provides a company brand domain name automatic query method and system. The query method comprises the following steps: firstly, establishing a domain name suffix database; then, combining the company brand name with each domain name suffix in the domain name suffix database, and adding a company brand domain name formed by combining the company brand name with each domain name suffix into the domain name database; and finally, querying and judging whether each company brand domain name in the domain name database is registered or not by utilizing a plurality of registration information query websites, so that the query stability and accuracy are ensured. According to the invention, rapid and accurate query of company brand domain names is realized.