Literacy and library are like Siamese twins that cannot be separated. Society draw literacy skills from the libraries the same way an individual draws from his memory to meet his immediate information needs. Examined in this paper is the relevance of literacy library to the functional literacy need of the 21st Century adult learners. Literacy library is conceptualised as a special library provision targeted at adult members of the society who have enrolled or willing to enrol in a learning programme. Key features of Literacy library are outlined, followed by brief description of specific materials relevant to the 21st century learning engagement of adult. Few studies on public library have focused on addressing problems facing adult learners in accessing library services. This paper recognised the fundamental role Literacy libraries can play in confronting the exclusion of adult learners in library provision and also provided useful insights to the peculiar nature of their literacy needs in their given context.