Compound nouns are independent lexical units and, therefore, they can not be directly translated on the basis of the translation equivalents of their constitutive units. In this article we propose a typology of translation divergences for compound nouns on the basis of a corpus of 25,000 translation equivalents French-Spanish. This typology take into account, on one hand, the ‘transparence’ degree in translation and, on the other hand, the differences between a French compound noun and its Spanish equivalent concerning the morphological form of this compound, the gender and number of its constituent units and the determination. It was observed that more than 25% of equivalent units in translation have some kind of divergence. © 1997 John Benjamins Publishing Company.