In recent years, with the rapid development of mobile Internet, the telecommunications industry has entered the mobile era. Against this significant background, companies can make use of the mobile Internet and converge communication traffic to expand into the mobile field. As an entrance to corporate communication, the significance of business contacts can't be ignored. However, the limited characteristic of mobile Internet resources has not been paid attention to by the update technology of traditional. As a result, it is no longer conducive to the current converged communications. Therefore, this paper puts forward an incremental update methods based on LDAP directory service in order to reduce resources consumed in the mobile client and server side. In conclusion, an experimental and comparative analysis of the full amount update technology used in traditional corporate directory and incremental update technology presented in this paper is conducted with an aim to verify and confirm that the incremental update method applied in the mobile Internet gains advantages over the full amount of update.