"Tim's knowledge of journalism and the critical role that news creators play in shaping the communities in which we live has been outstanding. He will step down with our very best wishes and leave the company on June 30."
In a speech to staff, Murphy said: "I've had a great, long and thoroughly rewarding time leading our journalism - with a tremendous group of journalists and friends. And I'm proud of our papers and site which, in an era of real industry upheaval, are performing strongly -- due to constant, at-times heroic, efforts by all of you.
"We've certainly done our best for our readers at every step. We've changed the Herald vastly in the past decade - both the paper and our digital voices.
"The opportunities for the Herald and our journalism are considerable.
"We're in good heart - a big voice, trusted and valued, and a constant in many readers' daily lives. In terms of newsgathering and dissemination, it really is a golden age. And that's what we're particularly good at. "
Murphy said he had decided the time is right to step down "while I still love what I do.''
"Thank you all for the support you've given me in these roles. Thanks for the sustained excellence of what you do and for the unique, positive spirit of this place."