The main cause of downgrading was it lost 0-1 to the Hong Kong team in the qualifying round of Asian Cup 2015.
Vietnam's biggest rival Thailand has also fallen five notches to 140th after being defeated 2-5 by Lebanon.
Even Singapore, champion of the Asean Football Federation AFF Cup 2012, has dropped three positions to 165th.
In Asia, despite its downgrading to 29th in the world's rankings, Japan remains in its top position, followed by the Republic of Korea (42nd), Australia (46th) and Iran (56th).
The top three in the world's rankings are Spain, Germany and Argentina.
Brazil, which is the host of World Cup 2014, has dropped to 19th after two draws in friendly matches with Italy and Russia.
Britain and Italy have fallen three notches to 7th and 8th, respectively./.
Source: DTNews