Romgaz reported a turnover of RON1.18 billion (EUR289 million), up 3.8% from RON1.14 billion in the first quarter of 2010.
Natural gas output stood at 1.51 billion cubic meters in January to March, down 3.8% on the year.
The company said total investments reached RON129 million (EUR31.4 million) in the first quarter, down from RON189.6 million in the year-earlier period.
Romgaz estimates its full-year net profit will rise to RON649.5 million (EUR158.2 million), from RON508.5 million in 2010.
The company is majority owned by the Romanian Economy Ministry, with an 85.01% stake. The ministry plans to sell 15% of its stake on the Bucharest bourse this year. (EUR1=RON4.1039)