The move comes as head of corporate relations Sophie Jones prepares to step down from her role after 12 years to "take a short break and pursue new opportunities", Channel 4 said.
MacLeod, previously head of press and publicity, will lead Channel 4’s corporate comms, public affairs and stakeholder activity, policy, internal communications and its content and programme PR at the new 38-strong division.
MacLeod has been Channel 4’s head of press & publicity since 2014, and before that was head of corporate press.
Previously he was head of press, broadcasting at ITV and has worked in a range of comms roles at ITV and BBC. He will continue to report to director of commercial affairs Martin Baker whilst long term reporting lines are finalised, Channel 4 said.
The broadcaster credited Jones, who departs at the end of the year, with playing a significant role in key projects including the formation of the 4AlltheUK plan to make sure the channel better represents all the country; its inclusion and diversity strategy; and securing the corporation’s public service licence.
Alex Mahon, Channel 4 chief executive, said: "Sophie has been a highly valued colleague, giving over a decade of service to Channel 4 and making a significant contribution to some of our most important projects. I’m immensely grateful for the support she’s given me over the last two years and we wish her all the best with whatever challenge she decides to take on next. I have no doubt she’ll make a great success of her next endeavour."
"I’m also delighted to be able to bring all of our communications and stakeholder activity together under James’ strategic leadership. James brings a wealth of comms expertise and experience from across the broadcasting sector and I'm looking forward to working with him in this important new role."
The news comes one year after the departure of Channel 4's chief marketing and communications officer, Dan Brooke.