Culture of a group is intricately intermingled with economic activities. Such a relation with economy and culture forms a distinctive pattern of social interaction, social relation and even social structure. This phenomenon is very much prominent in the Sundarbans, wherein living along the river side and engagement in fishing activity produce a distinctive form of cultural system. Such cultural system influences social relation as well as social structure of riverine environment. On the contrary, cultural system of the people staying away from the river differs due to practice of agricultural economy. So social relation and social structure of such location would be different from riverine location.