This study shows that M. oleifera (MO) grown in the Mediterranean area under drip-irrigation produced high forage mass (35 t DM/Ha/year). Lactating Holstein cows fed supplement of ensiled MO with solid additives (at level of 180 g/kg TMR DM) as wheat silage and hay substitute, were characterized by higher milk, FCM and ECM yields and improved ECM production efficiency compared with the control cows. Milk of the MO-fed cows was characterized by 20% more anti-oxidative activity. However, this dose of ensiled MO supplement impaired DM, and NDF digestibility of the cows, compared with the control group. It is therefore suggested to ensile mixture of MO with soy hulls or corn grains as higher digestible additive for lactating dairy cows.