Eero Einar Böök (1910 - 1990) was a Finnish chess player and engineer.

A six-times Finnish champion who represented his country six times in the Chess Olympiad, he was awarded the International Master title in 1950 and became an honorary Grandmaster in 1984. His significant international tournament victory was a tie for first place with Gösta Stoltz in the 1947 Nordic Championship in Helsinki. He played many of the world's top players, and managed to beat Paul Keres in the 1952 Helsinki Olympiad.