Supplementation of the mother's diet with antioxidants such as hydroxytyrosol (HTX) has been proposed to ameliorate adverse phenotypes of foetuses affected by intrauterine growth restriction (IUGR). Our previous studies showed, in a porcine model of IUGR, an effect of maternal HTX supplementation on the neurotransmitter profile of several brain areas and the morphology of the hippocampus in 100-days old foetuses. The present study analyzed the impact of maternal HTX supplementation on the hippocampus proteome at this foetal age by TMT10plex labelling. Eleven differentially abundant proteins were identified comparing both conditions, eight of them downregulated and three upregulated in the HTX-treated group. Downregulated proteins were mainly involved in protein synthesis and RNA metabolism, and may explain the differences in neuron differentiation in the HTX-treated group. Upregulated proteins were related to cell detoxification and could represent a potential mechanism to explain the neuroprotective effect of HTX.