There is an increasing interest in using cereal-legume intercrops mixtures in ruminant production systems to assist forage self-sufficiency and climate change adaptation. Available data on the energy value of the cereal-legume silages are limited due to a lack of in vivo organic matter digestibility (OMD) measurements and the potential vast number of mixtures used in practice. The objective of this work was to study the relationships between in vivo OMD and some chemical and enzymatic parameters of different cereallegume silages in order to identify a potential predictor for the OMD. Data from four trials with sheep carried out on the experimental farms of INRA Le Pin-au-Haras (France) and Agroscope, Posieux (Switzerland) were used. The cereals in the mixtures were oat, wheat or triticale, and the legumes were pea and vetch. Mixtures were harvested at two stages of growth. Significant relationships were observed between OMD and crude protein content, legume proportion and pepsine-cellulase digestibility (PCD). The best model to predict OMD used PCD (R2=0.71). Additional data with other mixtures and legume proportions are required to confirm this result, but PCD would enable the prediction of in vivo OMD of cereal-legume silages with good precision.