Alcoa recorded $308 million in net earnings for the three months to March 31, compared with $258 million the previous quarter and a loss of $172 million a year earlier.
Earnings per share came in at 28 cents, compared with 27 cents forecast by analysts.
Gross sales were up 5.4% to $5.96 billion from the previous quarter, and compared to $4.89 billion a year ago.
The company, one of the 30 members of the all-blue-chip Dow Jones Industrial Average, credited higher prices for alumina and aluminum, and growing demand for aluminum products in end-markets.
Alcoa said it expected global demand would grow by 12% in 2011 after a 13% rise last year.
"Our outlook for the rest of 2011 and beyond remains very positive due to the world's growing population, increasing urbanization, and aluminum's advantages as a light, strong and recyclable material," Alcoa chief executive Klaus Kleinfeld said.