He increased his majority from 3,339 to 7,528 in the first Senedd seat to be confirmed.
Plaid Cymru candidate, Elwyn Vaughan took second place and Liberal Democrat hopeful Alison Alexander was third.
Turnout for the constituency was 50 per cent, with 25,134 votes being cast.
Mr George, said: “It’s an absolute privilege to be returned as the Montgomeryshire member of the Senedd to represent my home constituency, where I was born and lived all my life."
He thanked the Powys County Council staff for conduction the election count in a “very difficult situation.”
Mr George also thanked his family and team for their support during the campaign as well as his fellow candidates who conducted a campaign that “focussed on policy.”
For the first time, Plaid Cymru came second in the constituency, which saw the Liberal Democrat vote fall by over 2,400 from 2016.
Plaid Cymru candidate Elwyn Vaughan, said: “This is the best ever result for Plaid Cymru in Montgomeryshire, we are the progressive force against the ultra right wing agenda by the Conservatives from London.
“That is the context unfortunately that we live in these days.
“I can assure you I will be staying in Powys politics to challenge and keep Russell and his team answerable and working hard for our communities.”
Mr Vaughan added that this result ensured that a Welsh voice had been heard clearly in the constituency which would be a base for the future.
Liberal Democrat candidate, Alison Alexander, said: “I can’t think of a time when liberal values could be more important.
“We have a lot of work to do here in Montgomeryshire and we are ready to do it.”
The final make-up of the next Senedd may not be confirmed until the weekend if results in some constituencies are close and recounts are called.
No party has ever won an outright majority in Wales, meaning the party which has won the most seats will be expected to enter into talks with other parties or independent members in order to form the next Welsh Government.
Voters will elect 40 members to represent constituencies, and 20 members to represent the five Welsh regions.