A public sector bank is a financial institution that is owned and operated by the government. These banks play a crucial role in the economy by providing financial services to individuals, businesses, and government entities. Service quality is a key factor in measuring the success of the banking sector. Banks understand how important it is to keep customers happy and to build and maintain strong, ongoing relationships with them, as this helps improve their overall performance. There is a noticeable difference in service quality between public sector banks and the different types of customers they serve. The objective of this study is to analyze the service quality in public sector banks, to find differences among demographics of customers and service quality in public sector banks, and to analyze the associated relationship between service quality in public sector banks and satisfaction of customers. A sample size of 130 was selected using a convenient sampling method. Primary data were collected from the customers in a public sector bank in kanyakumari district. The researcher chose public sector bank customers for the study. The findings reveal that customers perceive public sector banks as reliable and trustworthy, but also identify areas for improvement, such as customer service, technological infrastructure, and responsiveness to customer needs.