Earlier in the day, thousands streamed into Havana's Revolution Square to hear the Pope.
Security services were seen arresting at least three people who were shouting and attempting to distribute flyers at the edge of the square as the Mass got under way.
During his homily the Pope spoke of how "Christians are constantly called to set aside their own wishes and desires, their pursuit of power, and to look instead to those who are most vulnerable".
He also warned against ideology, saying: "Service is never ideological, for we do not serve ideas, we serve people".