Demand amounted to RON981 million.
Romania last sold September 2031 bonds in November at an average yield of 4.69%.
The government plans to raise RON5.3 billion selling state paper on the local market in December.
Romania's finance ministry on Monday rejected all bids on a bond issue maturing in September 2031, of which it planned to allocate 500 million lei (EUR104.6 million), central bank data showed.