Mylrea who has worked for Reuters since 1982, latterly as editor of AlertNet.org, has joined the charity as media manager heading global media operations in around 80 countries.
He is the first permanent media chief at the charity since the departure last September of Alison Vickers, who had the title of head of media.
Reporting to Mylrea is head of news Alison Woodhead who is responsibile for day-to-day work of the press office. Mylrea reports to campaigns director Adrian Lovett.
Oxfam last week launched a campaign calling for fair trade in the global coffee industry.
The charity is lobbying politicians and business calling for the destruction of surplus stocks to gain a fairer price for third world farmers.
AlertNet.org is Reuters internet service for global relief and development charities.