It was supposed, that xylene as environmental contaminant and chia (Salvia hispanica L.) as a medicinal plant may affect ovarian cell functions, and that chia seed extract could modify the potentially adverse effect of xylene. So, the aim of our investigation was to study the effect of xylene, extract of chia seed and their combination on bovine ovarian cell functions (proliferation, apoptosis and secretory activity) in vitro. Proliferation, apoptosis and the release of hormones (insulin-like growth factor 1 (IGF-1), progesterone and testosterone) were analysed with the use of either immunocytochemistry or EIA/RIA. It was observed, that xylene when given alone stimulated proliferation and did not influence the apoptosis. Furthermore, xylene inhibited release of progesterone and testosterone but did not change the release of IGF-1. Chia seed extract inhibited proliferation, apoptosis and the release of IGF-1, progesterone and testosterone. Moreover, chia seed extract suppressed the stimulatory effect of xylene on proliferation, and added together stimulated apoptosis. The simultaneous addition of chia seed extract and xylene stimulated IGF-1 release and inhibited the release of progesterone, but not testosterone. The obtained results prove a direct effect of both xylene and chia seed extract on bovine ovarian cell proliferation, apoptosis and secretory activity. Moreover, it is the first study in which chia seed extract was able to suppress xylene effect on ovarian cell proliferation. However, it prevented only from one xylene effect among five analysed suggesting that chia seed extract could not be potentially useful for natural prevention of all negative effects of xylene on reproduction.