Thousands of people, including the chancellor and President Joachim Gauck, were scheduled to attend the demonstration to be held in front of Berlin's Brandenburg Gate on Sunday.
Organized by the Central Council of Jews in Germany, the event coincides with a World Jewish Congress (WJC) meeting in the capital, and comes almost seven decades after the end of World War II, during which six million Jews were killed by the Nazis.
Speaking in her most recent weekly podcast, Chancellor Merkel vowed to "personally do everything I can - as will my entire government - to ensure that anti-Semitism doesn't have a chance in our country."
However, she also stressed that "we've got a lot of work ahead of us."
Spate of attacks
Over the summer, during Israel's military operation against the Islamist militant group Hamas in the Gaza Strip, there was a sharp increase in attacks on Jews, as well as anti-Semitic protests, in Germany. At the height of the bombardment in July, representatives of Germany's Jewish community described what they saw as an "explosion of evil and violent hatred of Jews" at pro-Palestinian rallies where some demonstrators chanted that Jews should be "gassed."
In one incident, a petrol bomb was thrown at a synagogue in the western German city of Wuppertal.
"We can see that there is not a single Jewish institution here that doesn't require police protection," Merkel said.
"That's something that very much concerns me," she added.
Foreign Minister Frank-Walter Steinmeier encouraged Germans to show their support at Sunday's rally, which is taking place under the banner, "Stand Up: Jew Hatred - Never Again!"
"Recent weeks have shown that anti-Semitism and racism rear its ugly head again and again in this country despite our dark 20th century history…we must resolutely confront this," Steinmeier told the newspaper, Ruhr Nachrichten.
Steinmeier is also to be the guest speaker at the JWC meeting in Berlin on Sunday evening. The group of up to 150 officials is convening to discuss the situation of Jews in Europe and Israel.
WJC President Ronald Lauder, who will also speak at the rally, said the number of attacks on Jews is much higher than those reported.
"A liberal country cannot and should not accept it when someone is attacked or maligned in the street because of Israel's policy," he wrote in this Sunday's edition of the mass-circulation newspaper Bild am Sonntag.
nm/pfd (dpa, Reuters, AFP, AP)