The US electric car manufacturer Tesla wants to deliver the first cars from the new Brandenburg plant in Grünheide on Tuesday.
At an opening ceremony (12.15 p.m.), Tesla boss Elon Musk, Chancellor Olaf Scholz and Federal Minister of Economics Robert Habeck will also be present.
Tesla received final approval for the plant in early March - but the first cars were already being manufactured there.
Tesla wants to have up to 500,000 electric cars built in the new factory every year, and a battery factory is also to be built.
The US electric car manufacturer wants to employ 12,000 people in its only European plant.
According to the Brandenburg state government, the third largest car factory in Germany is being built.
In the run-up to the opening of the new Tesla plant, the President of the Federation of German Industries (BDI), Siegfried Russwurm, praised the rapid completion of the project.
"The pace at Tesla must serve as a model for investment projects in Germany," Russwurm told the German Press Agency.
The intensive support from the state government accelerated the process considerably.
"German industrial companies would like this kind of support for every approval process in all federal states."
Tesla factory as a "flagship model"
Production was originally supposed to start last summer, but the approval was delayed - also because Tesla added a battery factory to the planning.
The project is considered a model for Brandenburg and all of East Germany.