Juan Adelarpe Alonso (13 December 1927 – 8 September 1994), sometimes called Juanito Alonso, was a Spanish footballer who played as a goalkeeper for Real Madrid and was part of their European Cup victories in 1956, 1957 and 1958. He earned two caps for the Spain national team. Alonso won the Ricardo Zamora Trophy during the 1954–55 season. At the end of his career he played a few matches for Real Madrid's second team, which then played under the name AD Plus Ultra in the second division.