Maria Valentina Galido Plaza (born June 1, 1967) is a Filipino politician who as served as governor and representative of the first district of the province of Agusan del Sur. She was the province's second female governor.
Plaza is the daughter of former governors Democrito Plaza and Valentina Plaza. She is also the sister of former governor Eddiebong Plaza and former congressman Rodolfo "Ompong" Plaza. She graduated from the University of the Philippines Los Baños with a degree in agricultural business.
Although a neophyte, in 2007, Plaza chose to run for governor of Agusan del Sur with the help of her brother Eddiebong Plaza. She won as the second female governor after her mother.
In the 2010 elections, Plaza was elected as the first representative of the newly created 1st district of the province of Agusan del Sur.