Muscovy duck in Indonesia has good potential to be developed as a meat producer, but currently its production and performance are still relatively low. additional feed is needed to increase it, such as cellulase enzymes, L-carnitine, and lemuru fish oil. where this combination, enzymes can increase nutrient digestibility, fish oil which is rich in unsaturated fatty acids and L-carnitine as a metabolic facilitator needed to oxidize long chain fatty acids. This research was conducted to investigate the effect of supplementing cellulase, carnitine and fish oil in feed on performance, EPA and DHA composition of Muscovy duck meat. In total, 120 Muscovy ducks in grower period were allocated to 4 dietary treatments with 5 replicates of 6 ducks. The treatments consisted of T0 = basal ration, T1 = T0 supplemented with 0.1% cellulase, T2 = T1 supplemented with L-carnitine 40 ppm, and T3 = T2 supplemented with 4% lemuru fish oil. The dietary treatments were fed for 90 days. The results of study showed that the effects of supplementing fish oil and L-carnitine in rations containing cellulase enzyme have a significant value (P<0.01) on the performance (feed consumption, daily body weight gain, feed conversion and IOFC) of male Muscovy duck grower phase and have a significant value (P<0.01) on EPA and DHA level in Muscovy duck meat. The supplementation can decrease feed consumption, meanwhile it increase daily body weight gain, improve feed conversion ratio, increase IOFC value, EPA and DHA level.