He begins his visit to this Eastern European country where Catholics do not reach 1 percent of the population.
Bulgarian Prime Minister, Boyko Borisov, greeted the pope at the base of the ladder at the Sofia airport.
Four children dressed in traditional costumes gave him bouquets of flowers as a sign of welcome.
There at the airport, in one of the salons, the pope held his first official meeting with the prime minister and received a pleasant surprise.
It is the 28th international trip of his pontificate.
Conversion to Christianity is prohibited in Morocco, but the pope thinks the situation is changing. He used the example of the Church who 300 years ago burned heretics and has grown in moral conscience.