Gap saw net earnings rise 51% to $229 million (£122.5m) for the second quarter ended August 2.
Gap said the profit hike was down to a combination of driving margin and managing costs but its second quarter sales fell 5% to $3.5 billion (£1.8bn). Like-for-like sales for the quarter were also down 10%.
Gap's International division, which includes its UK stores, saw like-for-like sales fall 6% over the period but total sales grew by 9.4% to $412m (£220.4m).
Gap chairman and chief executive Glenn Murphy said: "External conditions aside, we continue to deliver improved earnings with healthy margins and I am pleased with our second quarter results. While we continue to pursue our 2008 financial strategy, we are very focused on bringing more customers into our stores."