Count of Santa Cruz (in Portuguese Conde de Santa Cruz) was a Portuguese title of nobility created by a royal decree of King Philip II of Portugal, also known as Philip III of Spain, dated from October 3, 1593, and granted to Francisco de Mascarenhas (1530-1608), nephew of Dom Pedro de Mascarenhas, 6th Viceroy of Portuguese India.
Through a remarkable marriage policy, this family inherited several other titles and estates, such as Marquess of Gouveia in 1686, and Duke of Aveiro in 1745.
Beatriz Mascarenhas (1610–? ), 3rd Countess of Santa Cruz. She married a distant cousin, João de Mascarenhas (1600-1668), who became 3rd Count of Santa Cruz by marriage;
João Mascarenhas (1699–?), 7th Count of Santa Cruz and 4th Marquess of Gouveia, forced to renounce the title after fleeing Portugal for adultery, he chose to live maritally with his mother;
During the Brazilian Empire, there was also a title of Count of Santa Cruz, later upgraded to Marquis of Santa Cruz, granted to Romualdo António de Seixas (1787-1860), and it should not be confused with this Portuguese title.