‘Miwoo’ is a mid-late maturing, high-biomass-yielding rice (Oryza sativa L.) cultivar with high feed value and resistance to multiple diseases and insect pests. It was developed for use as whole crop silage (WCS) from a cross between ‘Suweon519’, a line with high biomass yield and multiple disease resistance, and ‘Suweon518’, a medium flowering, high yielding Tong-il type line, which is resistant to blast (BL), bacterial blight (BB) (race K1), rice stripe virus (RSV) and brown planthopper (BPH). In the central plain region of Suwon, ‘Miwoo’ cultivar exhibited a growth period of approximately 122 days from seeding to heading, culm length of 99 cm, panicle length of 28 cm, 12 panicles per hill, 143 spikelets per panicle, and 1,000-grain weight of 25.9 g as brown rice. This mid-late-flowering rice variety was resistant to lodging during the yellowing ripening stage, an optimal period for harvesting. In addition, ‘Miwoo’ was strongly resistant to leaf and neck blast, BB (race K1, K2, K3, K3a), RSV, BPH and small BPH. Its average dry matter yield over 3 years reached 19.9 MT/ha, which is 36% higher than that of ‘Nokyang’. ‘Miwoo’ is a high-amylose cultivar with 70.7% total digestible nutrients (similar to that of Nokyang) and grows well on the central and southern plains of the Korean Peninsula. It should be harvested 30 days after heading to improve its feed value and digestion rate in livestock. (Registration No. 7683)