Born in New York, Efraim moved to Israel in 1970 after completing his undergraduate degree in history (with honors) at Yeshiva University. He obtained a M.A. degree in Holocaust studies at the Institute of Contemporary Jewry of the Hebrew University, where he also completed his Ph.D., which chronicles the response of Orthodox Jewry in the United States to the Holocaust and focuses on the rescue attempts launched by the Vaad ha-Hatzala rescue committee. In 2000 Yeshiva University Press and KTAV Publishing House published his study of the history of the Vaad ha-Hatzala, which was awarded an Egit Grant for Holocaust and Jewish Resistance Literature by the Israeli General Federation of Labor (Histadrut) and also received the 1999-2000 Samuel Belkin Literary Award for the best book published by a Yeshiva University alumnus in the field of Jewish studies. 

In 1978 he was invited to be the first director of the Simon Wiesenthal Center in Los Angeles, where he played a leading role in establishing the Center’s library and archives and was historical advisor for the Academy award-winning documentary Genocide.

For the past thirty-seven years, he has played an increasingly important role in the worldwide efforts to find and help bring to justice Nazi war criminals. He began his career as a Nazi-hunter in 1980 when he was hired by the U.S. Justice Department’s Office of Special Investigations to be their sole researcher in Israel. During his six years in that capacity, his efforts assisted in the preparation of cases against numerous Nazi war criminals living in the United States.

In 1986 his research uncovered the postwar escape of hundreds of Nazi war criminals to Australia, Canada, Great Britain and other countries, and he rejoined the Wiesenthal Center to coordinate its international efforts to bring Holocaust perpetrators to justice. These efforts have influenced the passage of special laws in Canada (1987), Australia (1989) and Great Britain (1991), which enable the prosecution in those countries of Nazi war criminals.

Since the dismemberment of the Soviet Union and the fall of Communism, Zuroff has played a major role in the efforts to convince Lithuania, Latvia, and Estonia and other post-Communist societies to confront the widespread complicity of their nationals in the crimes of the Holocaust and to prosecute local Nazi collaborators. His public advocacy on these issues has been instrumental in the submission by Lithuania and Latvia of indictments (Lileikis, Gimzauskas, Dailide) and/or extradition requests (Kalejs, Gecas) against local Holocaust perpetrators. In 1991 he exposed the rehabilitation of Nazi war criminals in Lithuania and led the campaign to stop this process. Zuroff was appointed by the then Israeli Foreign Minister Shimon Peres to serve on the joint Israeli-Lithuanian commission of inquiry established to deal with this issue, which led to the cancellation to date of approximately two hundred rehabilitations granted to individuals who had participated in the murder of Jews during the Holocaust. In 2000 he exposed the rehabilitations granted by the Latvian government to Nazi war criminals and has led the efforts to cancel these pardons, two of which have been rescinded.

In the summer of 2002, together with Aryeh Rubin, founder of the Targum Shlishi Foundation, he launched “Operation: Last Chance,” which offers financial rewards for information which will facilitate the conviction and punishment of Nazi war criminals. So far, the project has been initiated in thirteen countries (Lithuania, Latvia, Estonia, Poland, Romania, Austria, Croatia, Hungary, Germany, Argentina, Chile, Brazil and Uruguay) and has yielded the names of over 540 hereto unknown suspects, one hundred and one of which have been submitted to local prosecutors. Additional information on this unique project is available at: www.operationlastchance.org.

Zuroff played an important role in the exposure, arrest, extradition and prosecution of Dinko Sakic, the former commandant of the Croatian concentration camp Jasenovac (nicknamed the “Auschwitz of the Balkans”). In early October 1999, Sakic who lived for more than fifty years in Argentina, was sentenced in Zagreb to twenty years’ imprisonment for his crimes in the first-ever trial of a Nazi war criminal in a post-Communist country, and he died in prison in July 2008.

In 2006, his exposure in Budapest of convicted but unpunished Hungarian Nazi war criminal Dr. Sandor Kepiro, who was among the officers responsible for the mass murder of at least 1,300  civilians in the city of Novi Sad, led to the current criminal investigation against him and focused attention on the highly-significant role played by Hungarian collaborators in Holocaust crimes.

In his first book, Occupation: Nazi-Hunter; The Continuing Search for the Perpetrators of the Holocaust (KTAV: Hoboken, 1994), Zuroff chronicles the belated efforts to prosecute Nazi war criminals in western democracies and explains the rationale for such efforts several decades after the crimes. A German-language edition was published by Ahriman Verlag in 1996. His second book Operation: Last Chance: One Man’s Quest to Bring Nazi Criminals to Justice (Macmillan: New York, 2009) summarizes almost three decades of Nazi-hunting and focuses on the renewed efforts spearheaded by Zuroff to hold Holocaust perpetrators accountable, in the wake of the breakup of the Soviet Union and the fall of Communism in Eastern Europe, as well as on the results achieved by "Operation: Last Chance."  A French-language edition was published under the title  Chasseur de nazis(Paris: Michel-Lafon) in late 2008, and a Serbian edition entitled Lovac na naciste (Belgrade: Zabor za udzbenika) appeared in November 2009. 

His activities as a Nazi-hunter were the subject of four television documentaries. The first, entitled The Nazi-Hunter, was produced by ZDF(German Channel 2) in 1999; the second, entitled The Last Nazi-Hunter was produced by SWR(German Channel 1-regional station) in 2004; the third The Final Hunt for the Nazis by France Trois(Channel 3)  was broadcast in December 2005; and the fourth The Search for Doctor Death, was produced by BBC in 2009. A fifth film, a full-length documentary by CNN, has been completed and is awaiting screening.

In 1995 and 1996, Zuroff was invited to Rwanda to assist the local authorities in their efforts to bring to justice the perpetrators of the genocide which took place in that country in spring 1994, and he has served as an official advisor to the Rwandan government.

In recent years, Zuroff has lectured extensively to audiences all over the world regarding the efforts to bring Nazi war criminals to justice. During the years 1992-1999, he served in the Education Corps of the Israeli Defense Forces (reserves) and lectured to thousands of soldiers about his work as a Nazi-hunter.

Over the years Zuroff has published more than two hundred and seventy-five articles, reports, and reviews on various topics relating to the Holocaust and other issues of concern in the Jewish world. His publications have appeared in scholarly journals such as Yad Vashem Studies, Holocaust and Genocide Studies, Simon Wiesenthal Center Annual, Jewish Political Studies Review, American Jewish History, and the Journal of Ecumenical Studies, as well as in the Los Angeles Times, Boston Globe, Jerusalem Post, The Independent, Tikkun, Jerusalem Report, Ma’ariv, Ha-Aretz, Yediot Achronot, Eretz Acheret, Jewish Chronicle, SHALOM, and other publications and have been translated into fifteen languages. The Simon Wiesenthal Center’s  “Annual Status Report on the Worldwide Investigation and Prosecution of Nazi War Criminals,” which Zuroff initiated in 2001, and which he has written every year since, is considered the authoritative source on the subject.

In recognition of his efforts as a Nazi-hunter and Holocaust scholar, he was nominated by Serbian President Boris Tadic and the members of parliament of the Democratic Party of Serbia as a candidate for the 2008 Nobel Peace Prize. In January 2009, he was awarded honorary citizenship of Novi Sad, the second largest city in Serbia, and in February 2010 he was given an official state decoration for his efforts to combat historical revisionism and neo-fascism by Croatian President Stjepan Mesić.