Critics say the human rights commission lacks teeth and is unlikely to be effective since Asean normally avoids interfering in the internal affairs of its 10 members, who include military-run Myanmar as well as Vietnam and Laos, both communist states.
Asean officials respond that the commission is a "work in progress" and can be strengthened in the future.
Rafendi Djamin, of the Asean Human Rights Commission, told Al Jazeera that the body will take some time to develop.
"Everything cannot be done instantaneously. Yes, criticisms will arise, but the need to pay attention to human rights is vital, and the commission will be in its development stages for some time to come," he said.
Members of the 10-nation bloc have, in recent weeks, escalated their criticism of Myanmar.
But the summit will again likely act by consensus, avoid confrontations and maintain that the group's approach to engaging Myanmar works better than sanctions and threats by Western powers.
The endorsement of human rights has been a challenge for Asean in the 42 years since it was founded to counter against the spread of communism.
| Security has been stepped up at the summit venue and in Bangkok [AFP]
Its members now include an absolute monarchy, a dictatorship and two communist states.
Myanmar has been Asean's "problem child" since it was admitted to the bloc in 1997, with the group under pressure from the US and EU to take a tougher line on Myanmar's military rulers.
In an effort to prevent a repeat of the disruptions that shutdown a meeting earlier this year, the Thai government has deployed more than 36,000 military and police both in Bangkok and the summit venue, officials said on Thursday.
The storming of the East Asian Summit in April in the coastal city of Pattaya, where anti-government protesters charged through thin police ranks, forced the evacuation of several leaders by helicopter and boat.
A main protest organiser told the Associated Press that no new demonstrations are planned in Bangkok or at Hua Hin.
About half of the security forces mobilised have thrown a security cordon around the conference venue, and the others will be on alert in Bangkok, Panitan Wattanayagorn, a government spokesman, told the Associated Press news agency.
He also said 20 newly bought bulletproof vehicles will chauffeur leaders to their meetings.