The Hollywood star said it's "fantastic" the actress - who he dated for almost three years - has received a Best Supporting Actress nod for Vicky Cristina Barcelona.
And Tom is hoping his former love walks off with the gold statuette at the ceremony, reports Extra.
The 46-year-old actor - now married to actress Katie Holmes - told journalists in Penelope's native Spain: "I am very excited by her second nomination. I hope she wins."
But Pen, who was nominated for a Best Actress Academy Award for her performance in 2007's Volver, faces tough competition.
The 34-year-old - who is now stepping out with actor Javier Bardem - will go head-to-head with Doubt stars Amy Adams and Viola Davis, The Curious Case Of Benjamin Button's Taraji P Henson and Marisa Tomei (The Wrestler).
The Oscars will take place at the Kodak Theatre in LA on February 22.