Library as a system, require measuring the performance at management level, financial level, infrastructure level, collection level and service level. Performance evaluation of libraries is necessary as it will help the library managers to identify key areas within the library which need urgent attention. The purpose of this paper is to identify the scope of improvement needed through the computation of Quality Index (QI) for a particular institution library using a Quality Index Model. The study will provide an opportunity in executing quality initiatives to enable better performances in libraries and on-going researches on evaluation mode of libraries.