the invention relates to a method of modeling reference data in an information system , characterized in that it is based on a unified modeling language model of reference data for the is listed in deposits of application data for the is . any reference data in the is is defined by a specialized concept inheriting the characteristics of a generic concept . the method comprises steps in which the following actions are carried out : grouping the concepts into categories according to logical criteria ; building a categories diagram in which the categories are grouped according to a predefined typing of categories , wherein the categories are related to each other by uml dependence relations , each materialized in one reference data ; making groups of generic concepts in the same category consistent with deposits of application data in the is by applying the principle according to which reference data defined by specialized concepts inheriting generic concepts in a same category and possessing an identical specialization necessarily belong to the data deposit of a unique application ; and defining a direction for uml dependence relations relating the said categories to each other , the said direction of uml dependence relations depending firstly on typing of categories , and secondly on the deposit of the reference data containing the relation .