Hancock will take up the post of head of PR, based in Sudan, from next week.
He will be responsible for communicating the charity's work in Sudan to international media and government representatives from donor countries.
He will also supply case studies for Cafod PROs around the world to make members aware of the difference their donations have made to the Sudanese people, and provide information for visiting donors in the region.
Leading a two-strong team, he will report to Sudan emergency co-ordinator Nick Wilson and Darfur emergency director Bjorg Mide.
'Although Sudan is going through a peace process, we need to make sure people do not forget that there is ongoing conflict in Darfur and that victims will need help to rebuild their lives,' said Wilson.
The move comes as Cafod expands its five-strong media team with two new posts and promotes senior media officer Fiona Callister to head of media UK.
Two press officer roles have been created to step up PR around specialist areas, including the tsunami crisis.
Callister replaces Martha Clarke, who is leaving on 5 May to begin a Masters degree in development work, and reports to Cafod head of advocacy and communications Alison Fenney.
'We want to get coverage for hidden emergencies and issues, such as the conflict in the Congo and the HIV/ Aids crisis, which form the core of our work but do not form the core of our media work,' said Callister.