Background and Aim: The purpose of this study was to investigate the extent of observing the standards of indexing (ISO 999-1996, BS 3700) of Library and Information Sciences books.

Method: The study used descriptive-analytical methodology and the population consisted of all the Persian books, written and translated, in the field of Library and Information Sciences published from 2006 to 2012 with the back-of-book index. To collect the data, a checklist based on the indexing standards of ISO 1996-999 and B.S. 3700 was used.

Results: The findings indicated that among the 424 books studied, 26% had index, while 71% lacks it. Overall, the extent of observing the evaluation criteria in the book indices in the field of Library and Information Sciences was 56%.

Conclusion: The results suggest that the extent of providing the index for the books in the field of Library and Information Sciences has a relatively optimal condition compared with those in other fields. However, considering the purposes and applications of the field of Library and Information Sciences, the standards in the indices have been poorly observed. Time-consuming nature of indexing, lack of time and accelerating pace of publishing and offering books, economic issues, lack of expert human resources, and lack of enough knowledge about the significance of index are some of the obstacles for preparing the index for the books.