Former Chelsea forward Loic Remy scored twice for the visitors, helping them become the first team to beat Los Che at their ground in the league since January 27.
Getafe opened the scoring on 16 minutes when Damian Suarez slipped a superb through-ball into the path of Remy, who curled an effort into the bottom-right corner of the Che net.
Marcelino Garcia Toral's charges then doubled their lead moments after the restart, Remy latching on to a pass from Jorge Molina on the edge of the penalty area and coolly slotting past Jaume Domenech.
Although Rodrigo halved the deficit on 69 minutes, finishing off after being played through by Martín Montoya, Valencia's fightback suffered a setback when Daniel Parejo's 86th-minute elbow on Molina was punished with a red card.
Valencia remain fourth in La Liga following the defeat, while Getafe climb to eighth in the standings, mathematically safe from the drop and still with outside chance of a Europa League place.
VALENCIA (4-4-2): Jaume; Montoya, Murillo, Garay, Gaya; Pereira (Torres 61'), Maksimovic (Soler 61'), Parejo, Guedes; Zaza, Vietto (Rodrigo 61')
GETAFE (4-4-2): Guaita; Damian, Bruno, Djene, Cabrera; Portillo (Mora 76'), Flamini, Fajr, Diedhiou (Antunes 90+2'); Remy (Jimenez 62'), Molina