Christian Solidarity Worldwide (CSW), which supports believers in countries such as Egypt and Nigeria, is being awarded Consultative Status after an eight-year wait.
CSW's Chief Executive Mervyn Thomas said: "This is a significant day for CSW. UN accreditation will enable us to advance our work of promoting the right to freedom of religion or belief across the UN system.
"This vote is also a welcome acknowledgment of the importance of NGO contributions to the UN's work."
CSW says the decision will open up "independent access to key UN human rights advocacy platforms" and offer it the "ability to organise side-events independently at fora such as the UN Human Rights Council (HRC) and UN General Assembly".
A decision on the organisation's bid for Consultative Status had been deferred for eight years before it was rejected by the UN's non-governmental organisation committee in February.
An appeal against the result was led by H.E. Matthew Rycroft CBE, Ambassador and Permanent Representative to the UK Mission to the UN in New York.
The permanent missions of the United States, Estonia (representing the European Union), Norway and Australia also made statements in support of CSW.
Subsequently, 54 nations on the United Nations (UN) Economic and Social Council (ECOSOC) decided to reverse the earlier decision.
Some 28 member nations voted in favour of granting Consultative Status to CSW, with nine voting against and twelve abstaining.
Mervyn Thomas added: "While we are pleased with the outcome of today's vote, the questions raised regarding the NGO Committee's tendency to repeatedly defer and deny the applications of human rights organisations need to be addressed."