It showed a set of communist symbols: a yellow hammer and sickle on a red field and, after official change of the flag's design in 1953, also an outlined yellow star, above a band of water waves near the bottom.

It too followed the style of the flag of the Soviet Union, with six spiky blue and white wavy stripes added to the bottom, a reference to the Baltic Sea.

During the period of foreign rule in 1940–1991, the Estonian diaspora and diplomatic service around the world continued to use the national flag of Estonia, whereas the use of the national tricolour and its blue, black and white colour combination was banned and punishable by law in the Soviet Union until 1988.

On the evening of 23 February 1989 the Soviet flag was taken down permanently from the tower of Pikk Hermann of the Toompea Castle.

It was replaced with the national blue-black-white flag on the next morning, 24 February, upon the 70th anniversary of the Estonian Declaration of Independence.