NE-CAP, formerly Make Poverty History North East, is lobbying the Government to take clear action to alleviate poverty in developing countries.
This includes promoting fairness in trade, debt reduction, increasing and improving aid, and addressing climate change.
The Rt Rev Justin Welby said the campaign aims were "very dear to my own heart and supportive of the Christian message".
He said he had become "acutely aware" of the challenge of poverty since becoming Bishop of Durham last November, and that he wanted to add his support to NE-CAP's call.
"Its action is a positive demonstration of the values of a strong moral society and care for the common good of the planet and its citizens," he said.
"I profoundly believe in the Christian Gospel imperative of care for those who are disempowered and in poverty and for a fairer and more just world."
The bishop pledged to support poverty alleviation in prayer and action, as well as through raising greater awareness in the churches and in the House of Lords.
"We all need to be doing more to promote that common good through positive socially responsible action and I am pleased to add my name to it," he said.
"I hope that through the work of this initiative we see a positive impact on the plight of the most needy in society both here in the North East and wider afield; I urge you all to get involved."