Though Macau and Taiwan are both multi-ethnic societies constructed of immigrants, which share a lot in common, the outcome of the ethnic consciousness seems to be quite different. There were no serious inter-ethnic conflicts either before and after Macau was returned to China, however, this was not the case for Taiwan, where serious conflicts took place. Through comparing aspects such as the social structure and ethnic consciousness in Taiwan and Macau, it is discovered that Macau promoted both its colonial and Chinese culture, and that the immigrants accepted the socio-economic developments in Macau, the ethnic differences did not elevate to the political level, resulting in a more harmonious inter-ethnic relation. The case of Macau implies that Taiwan needs to unravel the historical ties which led to the inter-ethnic conflicts and establish a common understanding between ethnic groups, so that its ethnic problem can be resolved.