Understanding customer' lifestyles important for banks because it will guide in determining marketing policies, such as services, pricing, service delivery and promotion decisions. From the customer' lifestyle, banks will know what kind of customers' attitudes, interests and opinions, so they also will understand what the costumer' needs and what services needed by them. For Islamic banks, customers understanding are important because, nowadays, the competition of the banks is not only with other Islamic banks but also with the well-established conventional banks offering Islamic products or services The aims of this research paper are to describe what factors underline the customer's lifestyle of both Islamic and conventional bank, to segment the bank customers based on their lifestyles and investigate the profile of each segments, to compare the characteristics of the segments, and to identify marketing policies based on the characteristics. The population of the study is banking customers in Indonesia, in which the researchers have used judgment sampling as sample selection. There were 186 customers of Islamic banks and 244 customers of conventional bank as respondents in this study. Statistical methods employed were exploratory factor analysis and cluster analysis. The finding of the study shows that there are twelve factor underlining the customers' lifestyle, namely: factor of fashion conscious, internet usage, sports spectator, financial and technology optimism, price sensitivity, independent, compulsive housekeeper, new brand tryer community activities, opinion leader, credit usage, and homebody. In addition, for Islamic banking, there are two market segments, namely fashionable-independent and innovative-social segment. Based on the lifestyle characteristics, the first segment has higher level in factor of fashion conscious, homebody, independent, optimism and price conscious, which is therefore called fashionable-independent segment. On the other hand, the second cluster has higher level in factor of new brand tryer, community minded, sport spectator, credit user, internet usage, opinion leader, and compulsive housekeeper, which is therefore called the innovative-social segment. Furthermore, for conventional banking, there are also two segments, namely persuasive-optimistic and sensitive-independent segment. The first segment has higher level on some factors, namely: opinion leader, optimism, internet usage rate, credit usage level, sport spectator, and new brand tryer. On the other hand, the second cluster is characterized by higher level in factor of price conscious, confidence, community minded, homebody, fashion conscious, and compulsive housekeeper. Managerial implications for the management of Islamic banks could be identified in this study as follows. Firstly, the twelve lifestyle factors of this study could be an alternative view in observe Islamic banking customers. The domination of both the fashionable conscious and the internet usage factor show that the aspects are quite instrumental in perceiving the customer' lifestyles, in which reflects the importance of these two aspects to customers. Secondly, in serving their customers, Islamic banks need to understand the customer lifestyle, in which the lifestyle segments found in this study provide a guide of how their needs were reflected. Finally, by understanding the segments and the characteristics each segment of the conventional banks, Islamic banks could adjust their marketing strategies differently from the conventional banks.