The Spaniard claimed his first title in his rookie season at the Bad Ragaz PGA Seniors Open.
He would add the 2007 Open de France Senior, 2008 Irish Seniors Open and the 2011 Cannes Mougins Masters to his record.
He made more than 200 tournament appearances on the DP World Tour, his best finish as runner-up in the 1994 Open de Tenerife.
As of September 2025, Juan Quiros has been actively competing on the Legends Tour, with his most recent appearances including a tie for 36th at the Reignwood Legends Championship on July 6, 2025, with rounds of 70–79–73 (+6), and a 55th-place finish at the Swiss Seniors Open on July 13, 2025, with a score of 214 (+4).