كتب : Megan Detrie
The Spanish goalkeeper conceded three goals in Liverpool's local derby defeat from Everton on Saturday, but Benitez insisted on backing his compatriot.
"I have a lot of confidence in Pepe Reina after he collected 33 clean sheets last season," Benitez was quoted as saying on Liverpool's official website.
Reina's form has put him under heavy criticism before Liverpool's opening UEFA Champions League Group C match against PSV Eindhoven on Tuesday.
"We don't need to talk a lot about him because he's a very good goalkeeper," Benitez told reporters on Monday.
The manager went on to call for improvement before Tuesday's game.
"We need to improve in defense, that is very clear, and it's good that after Saturday's defeat we have a game against PSV Eindhoven so we can put things right," he said.
However, while Benitez looks to improve his back-line, he faces the absence of Norwegian defender John Arne Riise due to his recurring ankle injury.
Benitez has added young defenders Daniel Agger and Gabriel Paletta to the list, neither of whom were on the bench during the derby match at Goodison Park.
Benitez may be gearing up to settle a personal score with PSV coach Ronald Koeman, who was in charge of Benfica last season.
Benfica's handiwork caused Liverpool's exit from the competition.