He also visited the emergency living quarters where many people affected by the disaster still reside.
“Have hope; we are moving forward,” the Pope said to those still struggling three years after the calamity.
“I am close to each of you, I pray for you, so that this situation may be resolved as soon as possible.
“Thank you for your patience and courage, and pray for me.”
Inside the cathedral, Francis was surrounded by fire-fighters and clergymen, also wearing helmets.
He placed flowers at a statue of the Virgin Mary, which was damaged in the earthquake.
The statue’s head and arms are missing.
The image of Francis wearing a helmet mirrored the scene in Paris on Saturday, of churchmen, including the archbishop of Paris, wearing hard hats as they celebrated the first Mass in Notre Dame Cathedral since a fire ravaged the landmark and toppled its spire on April 15.