The formal approval on Tuesday of the 41-member National Human Rights Association, which includes several women and has a mandate to monitor violations of women's rights, comes as the United States seeks to promote reforms across the Arab world.
But the Saudi government has rejected any political change "imposed from outside" and officials made clear the new organisation would be guided by domestic values in Saudi Arabia, the birthplace of Islam and home to its two holiest sites.
Association chairman Abd Allah al-Ubaid told the official Saudi Press Agency (SPA) his group would take as its authority the Quran, the sayings of Prophet Muhammad and the Saudi constitution, which is based on Islamic Sharia law.
Standing against 'opression'
The agency will work with other international human rights organisations and will stand against "oppression ... violence, torture and intolerance", according to its constitution published by SPA.
It will also receive complaints over human rights violations and follow them up with government bodies and offer suggestions and opinions to help develop the culture of human rights.
Ubaid and several other members of the group met de facto ruler Crown Prince Abd Allah on Tuesday. They also received a letter from King Fahd wishing them success.
Saudi officials have said the establishment of the body, which follows the first human rights conference in Riyadh last October, is part of a wider reform process in the kingdom.