The state-run company posted net profit of 199.3 million lei (EUR44.9 million) in January to March, compared with RON226.6 million in the same period of 2014.
The gross profit was also down 12% year-on-year, at RON238.7 million, according to the quarterly financial report of Transgaz.
The company posted total revenues of RON471.3 million for the first three months, down 11% from RON526.8 million in the year-ago period.
Transgaz said it transported a lower quantity of gas in the analyzed period, of 3.94 billion cubic meters, compared with 4.2 billion cubic meters in January-March 2014.
Wednesday morning in Bucharest, Transgaz shares traded down 0.6% in a stable market.