The study investigated awareness and use of online public access catalogue (OPAC) in university libraries by students of library and information science in the Niger Delta region of Nigeria. In carrying out this study, six research questions were raised and one null hypothesis were formulated and tested at P < 0.05. A questionnaire was distributed to 326 library and information science students in the five (5) universities where library and information science is offered. Three hundred and five (305) copies of the questionnaire were retrieved and found usable and thus formed the sample size of the study. The study revealed that 80% of users are aware of the OPAC and its services, however less than 30% of the students utilize its services due to varying challenges like insufficient computer terminals, poor network and power supply. Though, user’s general perception reveals that OPAC is easy, simple and faster for bibliographic information search and retrieval. However, satisfaction level was low due to reasons aforementioned. The study recommended that user education programmes on awareness and use should be introduced and university library management should provide more terminals for use amongst others.