The anti-Semitic rhethoric was suprising to historians since Truman, who was president from 1945 to 1953, helped Jews after the end of World War II and was a major supporter of the creation of Israel in 1948.
The Truman Presidential Museum and Library in Missouri said on Friday the remarks were on three loose sheets of paper which were found by staff as they reshelved books.
"The Jews, I find are very, very selfish. They care not how many Estonians, Latvians, Finns, Poles, Yugoslavs or Greeks get murdered or mistreated as (displaced persons) as long as the Jews get special treatment," Truman wrote on July 21, 1947 in his journal.
"Yet when they have power, physical, financial or political, neither (Adolf) Hitler nor (Joseph) Stalin has anything on them for cruelty or mistreatment to the underdog," he wrote.
The Truman Library said the former president made the remarks during a meeting with Henry Morgenthau, a Jewish former treasury secretary who served under Truman's predecessor, Franklin Roosevelt.
The Washington Post reported Morgenthau asked to speak with Truman when European Jews who were fleeing Nazi genocide were refused entry into British-controlled Palestine.
"He'd no business, whatever to call me. The Jews have no sense of proportion nor do they have any judgment on world affairs," Truman wrote.
"Henry brought a thousand Jews to New York on a supposedly temporary basis and they stayed," he added in the journal entry.