Thesauri are knowledge models commonly used for information classification and retrieval whose structure is defined by standards such as the ISO 25964. However, when creators do not correctly follow the specifications, they construct models with inadequate concepts or relations that provide a limited usability. This paper describes a process that automatically analyzes the thesaurus properties and relations with respect to ISO 25964 specification, and suggests the correction of potential problems. It performs a lexical and syntactic analysis of the concept labels, and a structural and semantic analyses of the relations. The process has been tested with Urbamet and Gemet thesauri and the results have been analyzed to determine how well the proposed process works. (C) 2016 Elsevier B.V. All rights reserved.