The union's demands include better working conditions, a 3.2% salary increase and a one-time "coronavirus bonus" of €600.
Train drivers in Germany have announced plans for a third major strike in a month following a dispute with the country's national railway.
The GDL union has called on workers to strike from 02:00 CEST on Thursday for five days. Freight train drivers are expected to begin their strike one day earlier on Wednesday.
The union is at odds with government-owned Deutsche Bahn over a number of issues, including pay increases and better working conditions.
This week's action is set to be the longest so far after train drivers twice previously went on strike for two days in August.
Thousands of commuters will likely be affected across Germany, as well as many travellers and tourists on vacation during school holidays in several states.
GDL said it was calling for a 3.2% salary increase and a one-time "coronavirus bonus" of €600, and that their demands were not being discussed.
"It is one of the longest industrial actions we are taking and we are doing it on purpose," said union leader Claus Weselsky in Frankfurt.
"We don't see ourselves ready or willing to take shorter industrial action, given the blocking attitude of Deutsche Bahn managers."
Weselsky has however stressed that indefinite strikes were not currently under discussion.
Deutsche Bahn has said that it was prepared to negotiate a "coronavirus bonus" for this year and called on GDL to return to the table, accusing the union of dividing the workforce.
GDL, which traditionally has concentrated on train drivers, is competing with larger rival union EVG to represent a broader range of railway workers.