Abstract: This experiment was performed with the purpose of investigating effect of additional blend of Saccharomyces cerevisiae and Lactobacillus acidophilus probiotics on growth, ruminal metabolism and plasma fatty acid profiles particularly Conjugated Linoleic Acid (CLA) in growing goats fed corn silage and selected the optimal levels of the probiotics for further study. Twenty-four growing crossbred (Thai native x Anglo-Nubian) goats that weighed (14.2±2.3 kg), aged about 6 months, were purchased and allocated to 4 treatments according to Randomized Complete Block Design (RCBD) with 6 goats in each treatment. The blocks were made by weight into heavy, medium and light goats and each of the treatments contained two goats from each of the blocks. The results displayed that g kg^-1 W^0.75 dry matter intake (p<0.05), average daily gain (g day^-1) (p<0.01) and feed conversion (p<0.05) were increased. At the same time digestibility of neutral detergent fiber (p<0.05), ether extract, acid detergent fiber and CP (p>0.05) as well as that of dry matter and organic matter (p>0.05) also were increased. In the mean time, ruminal average pH unaffected, but the NH₃-N and also plasma urea nitrogen (p<0.05), total volatile fatty acid (p>0.05) were raised, but propionic proportion (p<0.05) and butyric proportion (p>0.05) were reduced in concurrent with raise of acetic proportion and resultantly C2:C3 ratio (p>0.05). Protozoa number (p>0.05) was depressed contrasted to heighten total viable bacterial number. On plasma fatty acid profiles, total saturated fatty acids (p>0.05) was increased and contrasted with decrease of C15:0 (p<0.01), C16:0 (p>0.05) and C18-C22 polyunsaturated fatty acids (p<0.05 or p<0.01). In addition, the experiment proved that the supplemented probiotics was in force for heightening CLA (p<0.01); for raising desirable fatty acids (p<0.05); for reducing ratio of PUFA: SFA (p>0.05) and for raising ratio of n6:n3 (p<0.05).