About 54% of them said it was the right of every citizen to be vocal in this regard.
About 20% felt that voicing criticism of the government amounted to an attack on democracy.
Another 20% said negative talk about the government was a direct attack on the African National Congress.
The survey was conducted by consumer insights company Pondering Panda on January 23 and 24, shortly after the debate of the FNB "You can help" campaign.
The campaign, which is promoted through a television advertisement, features children reading their hopes for the country.
One of the children reads: "The challenges before us cannot be solved by money, petty politics, protests or violence. All the great things we've done, we've done by helping each other."
Around 2 328 people between the ages of 13 and 34 were interviewed nationally by cellphone in the survey. At least 35% of them said the government was making South Africa's problems worse.
Around 31% said the problems would not change under the current leadership, and 30% said the government had made progress in resolving some of the country's issues.
Pondering Panda spokesperson Shirley Wakefield said: "These results show that a substantial number of young people are disenchanted with a perceived lack of delivery and leadership within government." – Sapa