Joan Serra Llobet (8 July 1927 – 24 January 2015) was a Spanish water polo player who competed in the 1948 Summer Olympics. He was born in Sabadell, Catalonia.
He was part of the Spanish team which finished eighth in the 1948 tournament. He played all seven matches as goalkeeper. In 1951 won the gold medal in the Mediterranean Games. He died in Sabadell on 24 January 2015, aged 87.