Cataloguing and classification is the core of librarianship. Without cataloguing and classification, information materials in the library will be hardly accessed and retrieved. However, many librarians perceive cataloguing and classification as difficult, boring, and time consuming. Hence, this study was set to investigate the influence of work environment on librarians’ perception of cataloguing and classification in university libraries in Ogun State. A survey design of correlational type was adopted and the population comprised all academic librarians from the 14 universities in Ogun State. Total enumeration (census) was used, a structured questionnaire was used for data collection and the validity of the instrument was established by a Professor in the Department. 132 out of 144 copies of questionnaire were filled and returned, and then linear regression analysis was used for data analysis. Findings revealed that work environment has significant influence on librarians’ perception of cataloguing and classification in university libraries in Ogun State (β=.711, P<.05). Also, many librarians have low perception of cataloguing and classification with overall mean (X=2.2), factors such as difficulty of the job, boring nature of the practice and poor transfer of cataloguing knowledge to younger librarians cumulate to the poor and negative perception of librarians towards the practice of cataloguing. Inadequate power supply; low level of trained cataloguers, mentorship issues and epileptic supply of internet, constitute major setbacks for the librarians. Based on these findings, the study recommended that the management of each university library organize special training needed for the librarians within the area of cataloguing and classification; they should create a conducive and friendly work environment for the librarians, and a comprehensive administrative support and mentorship specially with regards to cataloguing and classification procedures, so that the associated challenges can be overcome for better performance of librarians on the job.