Iwan Lamby (October 29, 1885 – January 15, 1970) was a Swedish sailor who competed in the 1912 Summer Olympics.
He was a crew member of the Swedish boat Erna Signe, which won the silver medal in the 12 metre class.
Iwan's father Boris Roland Lamby, (1856-1893) was (unofficially) one of his mother's,
Wilhelmina (Mina) Lamby (1834-1863), 5 children with the Tsar Alexander II of Russia
Iwan is buried in a 10 m2 valve at the church of Klara in Stockholm.