The leader of the world's Roman Catholics called for a more compassionate approach to "people living through a real and dramatic exile, far from their countries, with the ruins of their own homes still in their eyes, fear in their hearts and often suffering from the loss of people dear to them.
"How is it possible that so much suffering can be inflicted on men, women and innocent children," the pope said at his weekly audience in St Peter's square.
Francis has regularly spoken out on Europe's migrant crisis. Last month he praised Greece's efforts in seeking to deal with the huge influx of people in a humanitarian manner and said other European countries should help to share the burden.
The pope has also urged every Catholic parish in the region to take in at least one asylum-seeking family. The Vatican is currently hosting two families.
The migrant crisis will dominate a summit of European Union leaders in Brussels on Thursday.