Last week, the German carrier canceled nearly 2,800 flights during a four-day walkout from Wednesday that affected more than 350,000 passengers, the 14th walkout in a dispute that since early 2014 has cost the carrier hundreds of millions of euros.
Lufthansa has offered to increase the pilots' pay by 4.4 percent in two installments and make a one-off payment worth 1.8 months' pay over a six year period.
Union Vereinigung Cockpit (VC) wants an average annual pay rise of 3.7 percent for 5,400 pilots over a five-year period backdated to 2012.
VC rejected the latest pay offer from Lufthansa late on Friday.
The pilots announced on Sunday plans to strike on short-haul routes on Tuesday and both short- and long-haul flights on Wednesday. Lufthansa said it was cancelling 816 and 890 flights on those days, respectively, affecting a total of around 180,000 passengers.
The carrier has asked a labor court in Munich to issue a temporary injunction to avert the strike, with a ruling likely due later on Monday. Last week, a labor court in Frankfurt rejected a similar request for an injunction.