Hoàng Tôn, Koo is a Vietnamese musical duo formed by singer Hoàng Tôn and rapper Koo, active in the Vietnamese pop and contemporary urban music scene in the 2010s. Their work blends pop, R&B and hip-hop elements, reflecting the trend in Vietnam toward hybridized mainstream and underground sounds that incorporate melodic vocal lines with rap verses and electronic production. The duo's recordings and performances emphasize polished studio production, accessible song structures and a focus on collaboration between vocal and rap roles, aligning with the broader commercialization of Vietnamese pop music during that period.