He said the parents should be allowed to do anything they can to get treatment for the baby boy.
Last week The European Court of Human Rights rejected a plea from Chris Gard and Connie Yates, to take their son to the US for experiential medical treatment.
It also ruled that the interim measure requiring doctors to continue giving life-support to the Charlie could be lifted.
#jesuisCharlieGard #charliesfight #letcharliegohome pic.twitter.com/tc0IwzTxyb
— Charlie's fight (@Fight4Charlie) June 30, 2017
The Vatican said the Pope followed "with affection and emotion the case of little Charlie Gard and expresses his own closeness to his parents".
Charlie is thought to be one of 16 children in the world to have mitochondrial depletion syndrome. The illness causes progressive muscle weakness and brain damage.
A statement from Greg Burke, Director of the Holy See Press Office, on Sunday said the Pope prays for 10-month old Charlie Gard's parents and hopes "that their desire to accompany and care for their own child to the end is not ignored."
Chris Gard and Connie Yates are spending the last days of their 10 month old son's life with him, after being given more time before his life-support is turned off.
"To defend human life, above all when it is wounded by illness, is a duty of love that God entrusts to all." @Pontifex pic.twitter.com/Tth3oHZo4v
— Charlie's fight (@Fight4Charlie) July 2, 2017
