He wrote several fictional novels that gave an unvarnished view of the Holocaust which were partly based on his own experiences in a Nazi concentration camp.

In 1941, at the time that he should have received an entrance card to higher education, he and his mother were interned in the ghetto of Mohyliv-Podilskyi (called "Transnistria") after German allied Romanian troupes took control of the region.

[2] According to Dagmar C. G. Lorenz, Simon Wiesenthal Center, Hilsenrath calls things by their proper names and portrays life first and foremost as physical existence, of whose details the reader is constantly made aware: birth, nursing, feeding, sex, and excretion accompanied by feelings of pleasure and pain.

In the novel The Nazi and the Barber, published in 1971 in the U.S., a German SS mass murderer, who later assumes a Jewish identity and escapes to Israel, describes the atrocities he committed.

For his novel The Story of the Last Thought on the Armenian genocide, Hilsenrath received the State Award in Literature of Armenia from its president.