The 10-member group's summit in Cambodia adopted the declaration, which officials described as an initial step in improving civil liberties, The Wall Street Journal reported.
"Given where ASEAN has been in the past in terms of human rights, I think this is a very important document that sets a number of expectations [and] standards," Indonesian Foreign Minister Marty Natalegawa told reporters Saturday.
Rights advocates say the declaration contains language that is not consistent with international law and allows governments to suppress rights by claiming the needs of security, public order or morality.
"This is a declaration of state power, rather than of human rights," said Yuval Ginbar, legal adviser to Amnesty International. "Under this document, governments can cite specific domestic conditions to justify rights violations -- this flies in the face of international law."
The ASEAN summit opened Sunday in Cambodia, with non-member Chinese and Japanese officials in attendance.
Delegations from Brunei, Cambodia, Indonesia, Laos, Malaysia, Myanmar -- formerly known as Burma -- Philippines, Singapore, Thailand and Vietnam were joined by Japanese Prime Minister Yoshihiko Noda and Chinese Premier Wen Jiabao, Japan's Kyodo news agency and China's state-run Xinhua agency reported.
Hosting Cambodian Prime Minister Hun Sen is the chairman of the summit this year.
He told reporters in Phnom Penh ASEAN members need to expedite efforts to reach group goals by the end of 2015.
"We have only slightly more than two years ahead to realize the ASEAN Community by 2015, while daunting tasks remain to be addressed," the prime minister said.
The group has set goals of easing tariffs in cross-member trade among its 600 million consumers, regulatory reforms and transportation, Kyodo said.
While neither Tokyo nor Beijing is part of the association, members are concerned of possible military response to an ongoing diplomatic tangle over ownership of several islands in the Sea of Japan, the reports said.