It is widely believed that identity with Taiwanese or Chinese is the major cleavage in Taiwan. People who hold Taiwanese identity tend to vote for the Democratic Progressive Party (DPP) and those who identify themselves as both Chinese and Taiwanese are likely to vote for the Kuomintang. As the proportion of Taiwanese identifiers increases, the geographical difference seems to persist. Whether national identity is associated with regional line and why they are correlated is a pressing question. This paper uses the 2012 presidential election survey data to explore the extent to which regional divide accounts for national identity. Using generalized linear mixed effect model (GLMM), this research finds minor regional divide in terms of ethnicity concentration and economic structure. However, ethnic background is influential on national identity while retrospective evaluation and democratic value are significant predictors. This mixed result suggests that people in Taiwan have united national identity should geographical difference remain or even decrease, and that we should remain watchful about the influence of democratic value and economic concern.