The leu opened at 4.348/4.349 per euro, almost unchanged from 4.348/4.3495 per euro at Wednesday closing.
It later weakened slightly in a quiet market, and traded at 4.3515/4.352 to the euro at around 10:30 local time (GMT0830).
The Romanian central bank set Wednesday the leu’s reference rate at 3.3467 per euro, little changed on the day.
On the money market Thursday morning, overnight rates were stable at 1.7%-2.2% a year.