Arthur Nory Oyakawa Mariano (born 18 September 1993) is a Brazilian artistic gymnast and a member of the Brazilian national team. He participated in the 2015 World Artistic Gymnastics Championships, placing fourth in the horizontal bar and 12th all-around. He won the bronze medal in floor exercise at the 2016 Summer Olympics in Rio de Janeiro. He is the 2019 World Champion on horizontal bar.