The appointment will see Quartermain join the likes of Peter Hitchener, Peter Mitchell and Ian Henderson as chief news presenters in Melbourne.
Walden is departing full-time television after more than 40 years. He is understood to be still considering less time-consuming TV projects for next year.
Handing on the baton, Walden said: “I could not endorse a more appropriate or more qualified colleague than Stephen to carry on the tradition of newsreader here at TEN.
“I have worked with Quarters for 25 years in the TEN Newsroom. We have both shared the same rights of passage through those years and the same passion for journalism. Now it’s time to hand over the baton as TEN News begins the next exciting phase of expansion.
“Stephen is as much a part of Melbourne as the AFL, so congratulations mate you will do us proud. I couldn’t be happier for you,” he said.
Quartermain said: “It’s very humbling to have the newsreader baton passed on to me. Mal is a legend of the Melbourne TV news business alongside names like Brian Naylor, Geoff Raymond and David Johnston.
“For 25 years we have been colleagues at TEN and have ridden a wild rollercoaster together! I have learnt a lot from Mal and admire the high standards he has set, his loyalty and his extraordinary longevity. He will be a hard act to follow.
“This is an exciting new phase of my career. I love the news business and hope to do the job proud,” he said.
TEN CEO Executive Officer, Hamish McLennan, said: “Everyone at Network TEN and all our viewers are sad to see Mal go.
“Mal is an institution, and no one can replace him. TEN News Melbourne’s success is a legacy he can be immensely proud of.
“Stephen is undoubtedly the right man to step into the job, and will deliver the credibility, integrity and class our viewers expect from TEN News,” he said.
TEN Head of News and Current Affairs, Anthony Flannery, said: “Mal is an undeniable legend of the business. Seeing him sign off for the last time will be a sad day.
“Mal is not just one of the best newsreaders to have graced our screens, he’s also a top bloke. We will make sure there’s a fitting farewell,” he said.
TEN’s Director of News Melbourne, Dermot O’Brien, added: “Stephen Quartermain is the ideal replacement for Mal Walden. Stephen is a highly credentialed television journalist and commentator, and after a long history on TEN News is a familiar face to our loyal viewers.
“TEN News viewers have come to accept the very best with Mal Walden and his handing the baton to Stephen allows for a logical and seamless transition on the news desk,” he said.
TEN today announced Brad McEwan returning home to become TEN Melbourne Sports Presenter, replaced by Matt Burke in Sydney.
“Brad McEwan’s return to TEN News in Melbourne means he comes full-circle to where his television career began. His sports knowledge is second to none and our viewers will remember Brad with genuine fondness,” O’Brien said.