Regino Sainz de la Maza y Ruiz (September 7, 1896 in Burgos – November 26, 1981 in Madrid) was a Spanish classical guitarist.
At age ten, he got his first guitar and started his musical studies with Santiago Landache (solfege), José Nicolás Quesada (piano), and Eugenio Rodríguez Pascual (guitar). Four years later, in 1910, his family moved to San Sebastián, where de la Maza studied piano with Germán Cendoya, harmony with Beltrán Pagola and guitar with Luis Soria. A year later he moved to Bilbao, where he studied with Hilarión Leloup. Aged eighteen, he performed at his first concert, at "Teatro Arriaga" of Bilbao.
He later moved to Barcelona, where he worked as a concert musician. There he befriended Miguel Llobet and Andrés Segovia. In 1920 he played for the first time in Madrid. A year later he toured South America, giving 90 concerts. On May 20, 1920 he was awarded a Golden Medal by the National University of Buenos Aires.
He befriended composer Antonio José Martínez Palacios, who dedicated his guitar compositions to Sainz de la Maza. He toured Europe, giving concerts in France in 1926, in Germany in 1927 and Great Britain in 1928. Five years later he toured South America for the second time; Uruguay, Argentina, and Brazil.
On December 19, 1930 he married Josefina de la Serna, daughter of the writer Concha Espina, at the Real Basílica de Monasterio de El Escorial.
In 1935, he was named professor of guitar at the Madrid Conservatory.
On November 6, 1940 he played the guitar at the premiere of Rodrigo's Concierto de Aranjuez in Barcelona conducted by César Mendoza Lasalle. Rodrigo dedicated the Concierto de Aranjuez to Regino Sainz de la Maza.
On December 11, 1940 he played the concerto in Madrid, with Jesús Arámbarri as conductor. In 1955 he published a book called "La Guitarra y su historia" (The guitar and its history). On May 23, 1958 he became a member of the Academy of Fine Arts of San Fernando of Madrid. A day later he was named favourite son of the city of Burgos.
He performed for the last time at the Church of San Nicola di Bari in Italy on July 9, 1979, aged 82.
His younger brother Eduardo Sainz de la Maza (1903–1982) was also an acclaimed guitarist and composer.