One item on the site was described as a striped uniform worn by a Polish baker who perished in the Auschwitz concentration camp.
The Daily Mail said a Ukrainian from Vancouver, Viktor Kemp, was asking $18,700 (Cdn) for the uniform.
Journalists working for the newspaper say they also found for auction yellow Star of David armbands used by the Nazis to identify and persecute Jews.
eBay has apologized for allowing the sale of the items.
The newspaper quotes Kempf as saying he bought the clothes from a reputable dealer in America and that he understands why people may think it's wrong to sell them.
He describes himself as a historian who realizes "these periods in history are horrific," and that "nobody should ever forget them."