The disclosure provides a domain name recognition method and a domain name recognition device. The domain name recognition method includes the following steps. A first string of a first domain name and a second string of a second domain name are obtained. Multiple characters of the first string and the second string are classified into multiple clusters. Multiple vectors corresponding to the clusters are generated, wherein each of the characters corresponds to one of the vectors. A first vector set corresponding to the first string and a second vector set corresponding to the second string are generated. A similarity of the first vector set and the second vector set is calculated.