Among those expected to attend the event are the presidents of Germany, Israel, Austria, Ukraine, Latvia, Finland, Switzerland, Slovenia, Slovakia and Malta.
Also taking part will be the prime ministers of France, Croatia, Greece, Sweden, Hungary, Romania, Serbia, Moldova, Lichtenstein, the Netherlands and the Czech Republic.
The United States will be represented by Treasury Secretary Steven T. Mnuchin.
The list of guests includes King Felipe VI and Queen Letizia of Spain, King Willem-Alexander and Queen Maxima of the Netherlands, and the Duchess of Cornwall.
Russia will be represented by its ambassador to Poland, Sergey Andreyev.
The event at the site of the former Auschwitz camp will be hosted by Polish President Andrzej Duda.
More than 200 former Auschwitz prisoners and Holocaust survivors are expected to come, including 120 from the United States, Canada, Israel and several European countries.