Marga Boodts (February 18, 1895 – October 13, 1976) was a woman who claimed to be Grand Duchess Olga Nikolaevna of Russia. She was one of a considerable number of Romanov pretenders who emerged from various parts of the world following the execution of Tsar Nicholas II and his family at Yekaterinberg on July 18, 1918. She stands out, however, as one of very few who claimed to have been Grand Duchess Olga, the Tsar's oldest daughter. She was also known as Maria Bottcher.