The traditional Taiwanese family structure is a controversial issue in family research. Past research by scholars has produced various results due to methodological differences. This research, which differs from previous studies, intends to delineate the internal split and reuniting processes within the family structure. The distributions of family structure from the Colonial Taiwan Household Registration Database is used to construct a Markov model, which analyzes the development of family structure in different economic status and ethnic groups. Findings show that households of different economic status have different development, and the joint families do not specifically limit to the minority of the rich. Last, the transitions of family structure in Minnan and Hakka households are very similar.