Matheson has been a senior press officer for the party in Westminster since January 2013, and worked with Scottish First Minister Nicola Sturgeon during this year's UK general election, and before that with previous First Minister Alex Salmond during last year's Scottish independence referendum.
She was previously a policy adviser in the European Parliament in Brussels, and a researcher in the Scottish Parliament, Edinburgh.
SNP Westminster leader Angus Robertson MP said: "I’m delighted Catriona will lead our new media team during this exciting time for the SNP in Westminster.
"Catriona has been on the front line of our referendum and general election campaigns, and for the past few months she has overseen the transition in the new parliamentary term for our enlarged group of new MPs."
The SNP National Conference 2015 begins in Aberdeen tomorrow.