The Information Science (IC) comes at a historic moment where doing science suffered decisive modifications regarding the integration of fields of scientific knowledge, seeking solutions to social problems that did not exist. It is interdisciplinary movement of knowledge. Therefore, the IC was born with a strong interdisciplinary inclination, and this aspect is the subject of several studies, both nationally and internationally. It is in this treadmill that this research is located, to conduct a study of interdisciplinary relations that Information Science has with other areas of knowledge from citation analysis article published in three national journals of important CI, Informacao & Sociedade: Estudos, Transinformacao e Perspectivas em Ciencia da Informacao. The reference lists of all articles published by those periodicals in the years 2011 and 2012 were analyzed. Each reference was classified, according to their subject, in consonance with the CNPq areas of knowledge table. The results showed that the CI uses theoretical contributions in many other areas of knowledge, notably Administration, Computer Science, Education and Sociology, as well as CI itself, which accounted for nearly half of all analyzed references. Apart from these, many other areas were used as theoretical support of the published works. Although the results observed in this study may not be conclusive, citation analysis proved to be an appropriate approach to the study of interdisciplinarity, which reveals that several areas have been contributing to research in IC.