‘Saekso 4’ is a high-yielding, anthocyanin-rich purple corn variety developed by the Gangwon State Agricultural Research and Extension Services for health functional food and processing materials. It was registered for variety protection in 2022. It is bred by crossing the inbred lines ‘HA7’ and ‘HA8’. ‘Saekso 4’ has a silking date of 71 days (2 days earlier than that of ‘Saekso 2’) and exhibits strong lodging resistance with an ear length of 18.6 cm. The grain is a bluish-black semi-flint with purple husks and cobs, making it highly suitable for biomaterial extraction. Notably, its grain yield reaches 832 kg/10a, a 49% increase compared with that of ‘Saekso 2’, exhibiting exceptional high-yielding capacity. Its grain anthocyanin content (170 mg/100 g) and absolute pigment yield were lower than those of ‘Saekso 2’. However, its superior overall productivity ensures a more reliable and consistent material supply for the bio-industry. Adapted to the Gangwon region, this F1 hybrid needs annual seed renewal and proper drainage management to prevent moisture damage. The dissemination of ‘Saekso 4’ is expected to markedly contribute to establishing a stable supply system for domestic green bio-materials and enhancing the incomes of farmers (Registration No. 8985).