Vatican visitors beamed with enthusiasm and Poles welcomed the decision, while some New Yorkers and Brazilians voiced concerns about old age and conservatism.
The BBC News website spoke to people on the streets of several world cities about their reactions to the election of Cardinal Joseph Ratzinger as the 265th pope.
Sister Rosvita, 35, nun, South Korea
"It's such a joy to be here.
"We have prayed for this moment and now we have hope, we have an anchor.
"Our new Pope will be a great leader. The fact that they elected him so quickly gives us a lot of confidence."
NEW YORK, US
Joseph Prete, 55, Chef
"I think he's kind of old to be pope.
"We couldn't waste any time in getting a new one and, although I don't know him at all yet, we will have to get used to it.
"At 78, that just seems too old to me."
SAO PAULO, BRAZIL
Nancy Grocetti, 32, teacher
"The Church needs to move out of the Middle Ages - away from this idea of a nobility within the clergy.
"And we should return to the essence of Christianity: love, solidarity and help for those in need. I wanted a Brazilian to get it - but in the end, I don't think nationality really matters."
Rafal Ziatek, 26, bookshop assistant from Warsaw
"I think it's a very good choice for the whole world. The new Pope will continue the policies of John Paul II. Benedict XVI will be conservative.
"I think it's very important for us in this time because the world doesn't need change, it needs some stability."
Zenalda Lopez, 70
"I welcome the news, the new Pope is very qualified so he is the right choice to lead the Catholic Church.
"I just hope he has compassion for the poor."