Migration is the common trajectory for most of the indigenous in Taiwan, but the social situations they encounter are totally different between the urban indigenous and those who stay in traditional areas. Instead of concentrating on the social problems urban indigenous might encounter, this paper focuses on the effect of social distance that migrants might experience and whether they can overcome the so-called ethnic boundaries. The research uses the data of the Taiwan Indigenous People Survey (TIPS) both to reveal those aspects of space distribution, employment status and social distance among urban indigenous and to elaborate the difference between the first and second migrant generations. The main findings are as follows: (1) the second migrant generation are much younger, better educated and have a higher probability of ethnic intermarriage and better job opportunities than the first generation; (2) the social contact with other ethnic groups has a positive effect on decreasing social distance between the indigenous and Han people; moreover the effect is more significant among the first generation than the second one; (3) the second generation is more likely to cross the social boundary than the first one; (4) for both generations, the effects of social contact and social distance on predicting the probability of ethnic intermarriage are both significant.