Trong, a conservative apparatchik, made the comments after being re-elected yesterday for a second term as top leader, bringing the five-yearly Communist Party Congress to a close with a resounding victory for the party's old guard following weeks of infighting.
The septuagenarian official, schooled in Soviet-style economics and seen as closer to Beijing than his erstwhile rival, Prime Minister Nguyen Tan Dung, used the first remarks of his new term to defend Vietnam's authoritarian system, which tolerates little dissent.
"With that in mind, who is more democratic?" he asked.
Trong's rival, the reformist Prime Minister Dung who is widely credited with pushing a pro-business agenda and had been tipped for the top job, lost out in internal elections and will step down in May.
More From This Section
His replacement is expected to be Nguyen Xuan Phuc, currently a deputy prime minister, state media said.
Trong has been party chief since 2011 and will stay on following a compromise deal which analysts say is a break from the charismatic Dung's decade in power and a shift back towards more consensus-based decision-making.
He sent a clear message in his speech that Vietnam, which is routinely criticised by rights groups and foreign governments for its intolerance of domestic dissent, will not be changing tack.
"A country without discipline, in chaos and instability, that country cannot develop. So democracy and discipline must go together," he said.
The country's new president, reported to be Tran Dai Quang by state media, is a police general who rose the ranks within the country's powerful Ministry of Public Security.