Family structure consists of family size and composition, family status and role, family power and authority, family communication and interaction and family relationship. These patterns of family structure are quite universal, and vary across the world cultures. Over the decades the empirical studies on the patterns of family structure have done are mostly culture-specific or specific content or perspective-oriented. This empirical book cross-culturally focuses on comprehensive multidimensional patterns of family structure between Muslim and Santal communities in rural Bangladesh. In so doing primary data collected through structural questionnaire method from both the communities, Kalna village, Bangladesh suggest that there are significant cross-cultural differences in family structure: family size and composition, family status and role, family power and authority, family communication and interaction, marital and family relationship. The findings would help behavioral and social scientists to understand cross-cultural family structure. The results would also help policy-makers and practitioners to design cross-cultural family welfare policy and programs.