Sime Seruya was born in Lisbon in 1876. She worked as an actress in Portugal before arriving in London in 1906. The following year she joined the Women's Social and Political Union (WSPU). In February 1907, she was sentenced to 14 days' imprisonment for taking part in a demonstration outside the House of Commons.
In 1907 some leading members of the WSPU began to question the leadership of Emmeline Pankhurst and Christabel Pankhurst. These women objected to the way that the Pankhursts were making decisions without consulting members. Teresa Billington-Greig pointed out the absurdity of women fighting for votes in an organisation that refused them a voice in their own campaign.
They also felt that a small group of wealthy women like Emmeline Pethick-Lawrence, Clare Mordan and Mary Blathwayt were having too much influence over the organisation. In the autumn of 1907, Sime Serya, Teresa Billington-Greig, Elizabeth How-Martyn, Dora Marsden, Helena Normanton, Anne Cobden Sanderson, Margaret Nevinson and Charlotte Despard and seventy other members of the WSPU left to form the Women's Freedom League (WFL).
In 1908 she joined the Actresses' Franchise League. Other members included Elizabeth Robins, Kitty Marion, Sime Seruya, Edith Craig, Inez Bensusan, Ellen Terry, Lillah McCarthy, Sybil Thorndike, Vera Holme, Lena Ashwell, Christabel Marshall, Winifred Mayo, Lily Langtry and Nina Boucicault.
Seruya was a member of the Independent Labour Party and in 1910 she attended the International Socialist Congress in Copenhagen.
Sime Seruya died in 1955.