Yki Nummi (1925 – 1984) was Finnish Lighting and Interior Designer. He was born in China.
Between 1945-47, he studied mathematics and physics in Helsinki and Turku. In 1946- 1950, painting, Taideteollinen Korkeakoulu, Helsinki.
1950-75, he designed lighting for Stockmann in Helsinki; his fixtures incorporated innovative materials, including coloured and white acrylics, opaline glass, aluminium, and brass. From 1958, he was head of the colour design department of paint manufacturer Schildt & Hallberg. In the early 1960s, he designed a colour plan for the Helsinki cathedral. He executed lighting designs for numerous firms in Finland and collaborated with Lisa Johansson-Pape as a colour specialist at Stockman/Orno in Kerava. He became an independent designer of lighting, furniture, and furnishings. He wrote several essays on colour, lighting, and design principles.
For his lighting, he won gold medals at 1954 (X) and 1957 (XI) Triennali di Milano. He received the 1971 Pro-Finlandia Medal. His work was shown at the 1954—57 USA ‘Design in Scandinavia’ travelling exhibition; 1955 ‘H 55° exhibition in Helsingborg, 1958 ‘Formes Scandinaves’ exhibition at the Paris Musée des Arts Décoratifs, 1956—57 West Germany travelling ‘Finnish Exhibition,’ and 1961 ‘Finlandia’ exhibition in Zurich, Amsterdam, and London.