The local chapter aims to represent the 3,400 US employees at a Mercedes-Benz plant outside of Tuscaloosa, Alabama, in the southern United States, and is being formed with help from German trade union IG Metal.
"This is the formation of a local union that will become the bargaining agent for workers at this facility," said Gary Casteel, UAW secretary treasurer and vice chairman of the Daimler workers committee.
"This isn't a petition for an election."
As membership roles grow, the UAW and IG Metal will pressure the company to accept the UAW as employees' bargaining agent, he said.
Mercedes-Benz opened the Tuscaloosa plant 20 years ago and the UAW has spent years trying to organize the plant without success.
The UAW already represents about 7,000 workers at Daimler truck plants in the United States, which are primarily located in North Carolina.
Michael Brecht, vice chairman of the Daimler AG Supervisory Board, noted during a press conference that the Alabama plant is the only Daimler factory without a union.
Workers at a Daimler truck plant in Chennai, India are currently in the process of setting up a union with the blessing of Daimler's management.
"The workers in Alabama are the only ones who don't have the support of a union," Brecht said.
"We are working with the UAW to change that."
Daimler officials emphasized that they saw no reason to change the structure of labour relations at the plant.
"Daimler has committed to stay neutral on the topic of labour representation and the choice to join a union is up to our team members," a company spokeswoman told AFP.