Premier Nguyen Tan Dung and 48 other high officials faced the test, the first of what will be an annual exercise aimed at showing the country that its leaders are accountable.
Dung's handling of the economy has put him under internal and public pressure. Last year he survived a leadership challenge. While the internal goings of the Communist Party are hard to read, many analysts said that Dung was under pressure from a clique close to President Truong Tan Sang.
Dung received 130 "low confidence" votes out of 498 ballots, the third highest number of negative votes cast.
The central bank governor received 209 "low confidence" marks, while the education minister got 177.
Sang got 28 "low confidence" votes.