Lufthansa reported an operating profit of €984m for the first nine months of 2008.
But the German national carrier said it expected a profit of around €1.1bn for the year, below its original forecast of €1.4bn.
The operating profit was 9.3% below the figure of €1,085m for the same period in 2007.
Its operating profit for the third quarter, from July to September, of €279m was also sharply down for the equivalent 2007 figure of €599m.
Wolfgang Mayrhuber
Net profit was also markedly down from €1.6bn in 2007 to €551m this year.
But the 2007 figure included €503m from the sale of shares in Thomas Cook and "book gains" of €82m from the repurchase of "own stock" by WAM Akquisition.
During the nine months, Lufthansa said its revenue had risen by 13.6% from €16,586m in 2007 to €18,596m this year.
The airline said the world wide slow down had been particularly felt in its passenger and catering sectors.
It added: "The sharp rise in fuel costs and strike-related losses, as well as the decline in demand caused by the state of the world economy, all had negative influences on the result."
Wolfgang Mayrhuber, Lufthansa's chairman and ceo, said: "This is a respectable result taking into consideration the considerable strains being felt as a result of the ongoing crisis in the financial markets and the overall economic situation."
"Crises are often the starting points for structural changes and we want to seize the opportunities that will present themselves to us in this situation to ensure the long-term consolidation of our position, whilst still maintaining our financial basis."
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