The Spanish stopper moved to Merseyside on a free transfer from Villarreal in 2005, two months after the 53-year-old had led the Reds to Champions League glory in Istanbul.
Reina has now reunited with Benitez at the Stadio San Paolo and has backed the coach to succeed in Serie A, despite a rough spell in charge of Inter Milan in 2010.
"Napoli remind me of Benitez's Liverpool," Sky Sports News quotes Reina as saying. "Despite the fact that we were not the strongest team technically, we were able to achieve great results due to hard work.
"I have found a similar Rafa to that of eight years ago. He has the same determination to do well and counts on the group and on hard work as the basis of success."
Benitez also won the 2006 FA Cup with Liverpool.