Bids amounted to RON259.2 million.
Romania last sold September 2031 bonds in September at an average yield of 5.23%.
The finance ministry seeks to raise RON4.2 billion selling state paper on the local market in October.
Romania's finance ministry on Monday raised 151.2 million lei (EUR32.45 million) from a planned RON200 million selling treasury bonds maturing in September 2031 at an average yield of 5.28%, central bank data showed.