Net profit fell 38 percent between February and April compared to the same three-month period a year earlier, to 171 million Swedish kronor (€18.4 million, $21 million), the airline said.
Sales dropped five percent to 8.9 billion kronor, it added.
"The weak results were primarily attributable to three factors: increased price pressure, technical maintenance costs and negative currency effects," SAS president and chief executive Rickard Gustafson said in a statement.
Shares in SAS fell more than 11 percent in early trading on a slightly lower Stockholm stock market.
Passenger numbers rose however and the airline saw a 5.7-percent rise in its seat occupancy rate, it said.
The quarterly results came as Swedish SAS pilots threaten to go on strike. A similar threat from SAS pilots in Norway was averted at the last-minute.
SAS is fifty percent owned by the Danish, Norwegian and Swedish states.