Prime Minister John Key is visiting Berlin's Memorial to the Murdered Jews of Europe, saying he is doing so "for mum".
Mr Key's Jewish mother Ruth fled Vienna as a schoolgirl and later emigrated to New Zealand.
Mr Key, who is not a practising Jew, said the Holocaust affected his mother deeply, Fairfax reported.
"She never talked to me about it, never talked about family, I can't really tell you who went and who didn't, other than that she lost people," he said.
The memorial in Berlin is to the Jewish victims of the Holocaust.
Mr Key has been in Europe after attending the Queen's diamond jubilee celebrations in London.
He discussed the eurozone crisis, Afghanistan and Syria during a lunch with German Chancellor Angela Merkel.
At a joint press conference with Mr Key, the German chancellor said Spain hasn't applied for euro region aid and Germany won't apply pressure on any state to do so, Bloomberg reported.