Helena Kmiec, who was working with the Salvator Missionary Volunteering group in Cochabamba, was stabbed to death on Tuesday.
The attack took place in the early hours of the morning after robbers broke into the centre run which is run by Polish nuns.
Fr Adam Ziolkowsski, director of the volunteer group told Vatican Radio that other volunteers were woken up by Kmiec's screams.
He said that it appears as if Kmiec had "tried to defend herself and she was stabbed repeatedly" on her hands, arms and chest. She died from her wounds at the scene.
"She was a kind person and very helpful; she never missed a chance to do something good for others" he said.
Kmiec had only arrived at the centre two weeks prior to the attack. She had planned to volunteer there for six months.
The Polish Ministry of Foreign Affairs said that Bolivian police had detained a number of suspects.