Aimed at measuring the sense of Urban Identity among megacities，this survey investigated a large number of people through the Mobile Internet，by the method of Snowball Sampling. Based on those over-10-million-resident megacities，divided into Cultural Identification，Identity Identification，Status Identification and Regional Identification，the goal has been well reached. As it turned out，after controlling the influence of Demographic Variables，such as age，income and profession，these megacities’ Urban Identities showed significant differences. The Core Influential Factors，discovered by the survey，is not the economic development level，but the Household Registration and the Urban Acceptance. All in all，this survey has provided an effective new index system to evaluate the development and construction of the new-type Urbanization，from the perspective of social identity.