The purpose of the present invention is to provide a feed additive composition for ruminants, the feed additive composition containing 30 wt% or more of a biologically active substance, being a dispersed type which is highly protective in the lumens, and exhibiting excellent dissolution in the gastrointestinal tract. The present invention pertains to a feed additive composition for ruminants characterized by containing (A) at least one selected from among a hydrogenated vegetable oil and a hydrogenated animal oil, which have a melting point higher than 50°C and lower than 90°C, (B) 0.05-6 wt% of lecithin, (C) at least 30 wt% and less than 65 wt% of a biologically active substance, (D) at least 0.01 wt% and less than 0.8 wt% of a natural vegetable oil, and at least 0.1 wt% and less than 6 wt% of water.
