The purpose of this study is to emphasize the reasons why manual classification of information materials should not be abandoned in current ICT era, particularly in Nigeria. Libraries are no exception to ICT applications, and we can observe how they have already altered library services and activities. Also, Information Technology (IT) has made it presence in almost every sphere of human activity including the library practice but to have fully automated classification scheme is yet to be implemented. Library operation, such as cataloging, reference service, and the rest has a feel of this. For example, ICT has incorporated copy cataloguing into cataloguing operations, which libraries now employ instead of manual cataloging and also the arrival of online public access cataloguing (OPAC) was influenced by ICT, but this has not been fully infused into classification operations, which has kept the manual system of classification alive even in the face of ICT. Manual classification, on the other hand, cannot be abandoned because it is fundamental to the profession of librarianship. The classification of information resources is a foundation upon which librarianship is built, making classification a system as old as the library itself, as well as a practice that is unaffected by technological innovation. In addition, there are a variety of reasons in Nigeria that support the continued use of manual classification of information resources in the face of ICT. As a result, in this study we attempted to see the necessity of manual classification as well as the limitations of ICT in classification and the availing of manual classification in Nigeria.