Alda Bandeira Tavares Vaz da Conceição (born September 22, 1949 in Santana, São Tomé) is a politician in São Tomé and Principe.

Bandeira was a founder of the Democratic Convergence Party-Reflection Group, which won legislative elections in 1991. She served as foreign minister from 1991 until 1993. In 1996 she ran for president of the country, receiving third place and 15% of the vote. She then served as president of her party for several years. In April 2002 she was appointed foreign minister again, but resigned later that year. She is married to former prime minister Norberto Costa Alegre .