In the technologies and means of recovery, storage and dissemination of information have produced several changes that had encouraged university libraries to seek resources and tools that fit that innovation to give users access to scientific information. This is possible using resources other than printed forms, which through the user has new options to find the information that can fulfill his expectations as researcher. These resources that support to the libraries to transmit the scientific information are electronic resources, which use tools as the search engines and metasearch engines, that allows the finding of this resources in the Internet. But nowadays, in the market exist technology tools complex, that allows to the searcher perform simultaneous searches through all electronic resources avalaible in the library, known as Federated Search Engines. Federated Search Engines should had some qualities, characteristics and functions that fulfill the needs of a university library and the prospects of the users as generators of knowledge. Therefore It’s important evaluate those tools using criteria, to establish which is the most suited for a library in terms of: material, financial and human resources, and allows the entire university community search and recovery of relevant and consistent scientific information. All this with the final porpouse of implementation and encouragement of the development of research.