The aim of this study was to evaluate different concentrations of olive oil for cryopreservation of boar semen. A total of 21 eyaculates of 18 males with motility ≥70% were used. For freezing, the semen was diluted in treatments: control (Cont–egg yolk), “Koroneiki” oil in egg yolk at 0.25% (A025), 0.50% (A050), 0.75% (A075) and 1.0% (A10). Straws with 5.107 sperm/ml were frozen and stored in liquid nitrogen. Thawing was done at 37ºC for 30 seconds and motility, mitochondrial functionality, DNA integrity, oocite penetration rate and the number of sperm per oocite (in the in vitro penetration trial) were evaluated. The variables were compared using the Kruskal-Wallis test. Even though no statistical difference was found between control and treatments containingolive oil (p>0.05), the treatment with 0.25% oil concentration showed tendences towards sperm protection, outperforming the controls in mitochondrial functionality and preservation of the fertilizing capabilities in the in vitro penetration trial. This is why, olive oil could represent an alternative to help cryopreservation of boar semen.  DOI: http://dx.doi.org/10.21615/cesmvz.11.1.1