Downing Street confirmed that the Queen had approved the nomination of the 64-year-old to take over the running of the diocese.
She takes over from Rt Revd Martin Wharton after he retired on 30th November 2014.
It's likely she will take a seat in the House of Lords after the rules were changed to accelerate the number of woman bishops who enter the chamber.
She said: "I don't really have the words to express my excitement at coming to this vibrant, warm and proud part of the world.
"From my own faith journey I know the key significance of warm, lively, welcoming church communities with worship that transforms us and sends us out into the world - bringing the depth of Christian hope to places where hope is thin on the ground.
"God cares about the world - not just about the Church. The rule of Christ is over the whole of our lives. That's why it's so important for Christians to engage and work with key partners for all that leads to the flourishing of communities. As Bishop of Newcastle I will take every opportunity to engage in the public square and especially to speak on behalf of those whose voices are not heard.
"It will be such a privilege to be your Bishop and to lead you on the next stage of the journey. In all of this I will be relying on God's grace and your prayers."
Ven Christine Hardman announced as new Bishop of Newcastle at Northumberland CofE Academy pic.twitter.com/gka5WyJAzL
— Arun Arora (@RevArun) September 2, 2015
The Ven Christine Hardman was ordained Deacon in 1987 and served her title at St John the Baptist, Markyate Street in the diocese of St Albans. She took up the role of Course Director on the St Albans Ministerial Training Scheme in 1988 and was appointed Director of Mission Studies in 1991.
She is married to Roger and they have two adult daughters, Elinor and Isabel.
Her interests include making connections between the worlds of economics and Christian faith, theatre, being in the mountains and cycling.
She is the seventh woman bishop to be appointed in the Church of England.
The Right Reverend Frank White, Assistant Bishop of Newcastle, said: "This is such a good moment to welcome Christine Hardman to be our new bishop and I look forward with eager anticipation to serving alongside her.
"Her wide interests and experience, and her desire to encounter and learn from the spirituality of this region, offer us all real opportunities for growth."
The Diocese of Newcastle covers an area from the River Tyne to the Scottish Border and includes the city of Newcastle upon Tyne, the county of Northumberland, North Tyneside and small areas of Cumbria and County Durham.
Bishop Christine said: "I've always known that the North East... has a reputation for warmth and hospitality, but you've exceeded the reputation, it's been fantastic, it's been wonderful!"
Listen to Premier's Ian Britton speak to Bishop Christine and Bishop Frank, Assistant Bishop of Newcastle here: