Eero Aarnio (born 1932) is a Finnish interior designer, well known for his innovative furniture designs in the 1960s, notably his plastic and fiberglass chairs.

Aarnio studied at the Institute of Industrial Arts in Helsinki, and started his own office in 1962. The following year he introduced his Ball Chair, a hollow sphere on a stand, open on one side to allow a person to sit within. The similar Bubble Chair was clear and suspended from above. Other innovative designs included his floating Pastil Chair (similar to a solid inner tube), and Tomato Chair (more stable with a seat between three spheres). His Screw Table, as the name suggests, had the appearance of a flat head screw driven into the ground.