Leo Wainstein (4 January 1883 – 13 March 1978) was a Ukrainian Jewish jurist and businessman who lived most part of his life in Finland. Wainstein was born in Yalta to a Jewish peasant family. He graduated as a jurist in Odessa University in 1910 and worked in the field until 1916 when he got involved in the wool business through his marriage to Regina née Tilling. After the October Revolution the couple moved to Finland, where Wainstein made a successful career in the textile industry. His business started to decline in the 1950s, and after this, he changed to hat industry for a few years before his retirement.