Ver.di union said in a statement Friday that airports across the country, including Frankfurt, Hamburg, Munich, Stuttgart and Cologne will be affected by the one-day strike Monday.
Lufthansa says it will have to cancel flights but had not yet worked out a new flight plan with specifics.
Lufthansa on Wednesday rejected the union's demand for wage increases of 5.2 percent over the next year and job guarantees.
Short-term warning strikes are a common tactic by German unions to raise pressure on employers during wage negotiations. The next round of talks is scheduled for April 29.