Public libraries are the reservoirs of human civilizations. They shoulder the great responsibility of colleting, organizing, storing and disseminating the human knowledge over the generations. The present study aims at exploring how the users of district central libraries of southern districts of Tamil Nadu State, India are using the libraries in general and library services, in particular. Survey method was employed. Random sampling technique was used to draw 150 participants. Questionnaires were used to collect the data. 149 responded. The study reveals that : about two third of them (96, 64.4%) are male users ; About half of them (74, 49.7%) are UG degree holders; More than half of the respondents (81, 54.4%) visit the library daily while 28.9% (43) of them visit the library once a week and the least percentage of students (25, 16.8%) visit the library twice a week ; A majority of the respondents, say more than two third, (104, 100%) spend more than two hours in the library a week ; one third of them (32.2%) have 3-5 years of experience in using the district central libraries ; a majority of the users visit the libraries to read newspapers and magazines; a majority of 61.7% of the respondents regularly use Circulation service of the libraries. One third of them (32.2%) regularly make use of TNPSC free coaching conducted by the sample libraries. 30.2% of them regularly use reference service of the libraries ;More than one third of the respondents (37.6%) felt high impact of library services on their reading and learning skills while one fourth of them (24.2%) felt high impact of library services on their self-development skills.Three fourth of the respondents (113, 75.8%) opined that the library services are adequate.Two third of the respondents (98, 65.8%) strongly agree that there encounter the problem of insufficient internet / ICT service in the district central libraries while slightly more than one fourth of them (42, 28.2%) strongly agree that the libraries don’t have adequate facilities. The variables – Gender, Educational qualification and Marital status – have a significant impact on their use of library services.