The purpose of the present study is to know the available reference sources and reference services provided by the select CSIR laboratory libraries situated at Delhi. The author use survey method and use questionnaire as a tool for data collection. A total number of 5 questionnaires personally distributed to the library In-charge and received total 5 questionnaires. The major findings of the study revealed that CSIR-NISCAIR library has highest number of collection i.e. 250000 and also has highest number of reference collection i.e.50000. All the select libraries have encyclopedia, dictionaries, government documents, yearbooks and Annuals in their reference collection in print form. In electronic form most of the library have abstract & index and standard. All the select libraries except CSIR-NISTADS offered DRS to its user. E-mail reference services provided by all the select libraries except CSIR-NISTADS and the provision of others modes of DRS are vary from library to library. The select libraries aware its users to make use of reference sources and services through promotional activities and through interaction with users. The major problems faced by the select libraries is also varies from library to library.