The index lost 0.12 point or 0.34% to close at 35.01.The gauge started with given mark of 100 on June 24, 2009 but it has never been back to that level.
The market volume fell to 372,600 shares changed hands for VND3.59 billion, compared with 544,294 shares changed hands for VND4.19 billion on Wednesday trading.
However, the market breadth was positive with 17 gainers, 16 losers, 8 unmoved and the rest untraded.
ADP was the biggest gainer today, climbing VND900 to close at VND10,000/unit on a trade of 500 shares.
DBM was the biggest loser today, giving up VND1,300 to close at VND18,500 with 1,900 units changed hands.
UDJ was the most active stock for the fifth consecutive day today with 82,300 shares traded, adding VND400 to hit the ceiling at VND10,600/unit.
Foreigners bought 1,900 BDM shares ;5200NTW shares; 60,000 WSB shares today.