This study investigated the influence of Petroleum Engineers' personal characteristics as determinant factor on their utilisation of information resources in Libraries of petroleum industries in south-south, Nigeria. The characteristics are working experience and field of specialisation. The survey was guided by three research questions and two hypotheses which were formulated for testing. The population of the study consisted of 1572 engineers in Exxon Mobil, Eket, Akwa Ibom and Agip Oil Company in Port Harcourt. The sample consisted of 499 respondents drawn from petroleum, mechanical, computer, electrical and other engineering fields in Exxon Mobil, Eket and Agip Oil Company in Port Harcourt. A 40-item researcher developed instrument called: Personal characteristic of Engineers and Information Resources Utilisation Questionnaire (PCEIRUQ) was used for data collection. The instrument has a reliability index of 0.95 using Cronbach's alpha coefficient. Data generated were analysed using Analysis of Variance (ANOVA). The results showed that information resources available in decreasing rank order are books, datasheets, project drawing, manuals, reports, CDs, information from colleagues, seminar/ workshops/ conference, internet and maps. Findings indicate that engineers' experience and fields of specialisation have significant (P<0.05) influence on their utilisation of information resources available in the petroleum industries. The table showed that mechanical engineers, with means score of 66.17 use the highest users of available information resources in their respective petroleum industries Libraries. These are closely followed by computer engineers (Mean = 64.12); Petroleum engineers (means = 63.39), in deceasing rank order. These observations showed that mechanical, computer and petroleum engineers are the top 3 users of information resources in petroleum industries. Newly employed engineers (mean = 65.89) were also observed to utilise information resources more than their experienced counterparts (mean= 65. 53). Recommendations was made that all engineers should