Labour Party member of Parliament (MP) for Ogmore since 2002. In the most recent election in 2015, Davies retained his seat with 53 percent of the vote and a majority of 13,043. 
Irranca-Davies has been the shadow minister for environment food and rural affairs since 2011.
Irranca-Davies has held positions as:
- Assistant Whip (HM Treasury) 2006-07
- Parliamentary Under-Secretary (Wales Office) 2007-08;
- Parliamentary Under-Secretary (Department for Environment, Food and Rural Affairs) (Marine and Natural Environment) 2008-10;
- Shadow Minister (Marine and Natural Environment) 2010-10; Shadow Minister (Energy and Climate Change) 2010-11;
- Shadow Minister (Environment, Food and Rural Affairs) 2011-.
- All Party Parliamentary Group on Unconventional Oil and Gas, member
- All Party Parliamentary Group on Climate Change Group - Vice Chair
- All-Party Parliamentary Group on Freedom of Religion or Belief 
- All-Party Parliamentary Group on Water Safety and Drowning Prevention, member 
- All-Party Parliamentary Group on Science and Technology in Agriculture - Vice-chair 
- United Kingdom Overseas Territories All-Party Parliamentary Group - Vice-chair
- Associate Parliamentary Food and Health Group - Vice-chair 
- Huw-Irranca-Davies,parliament.uk, 12 November 2015
- Winning candidates for select committee Chairs announced, www.parliament.co.uk, 18 June 2015
- Huw Irranca-Davies, www.parliament.uk, accessed 17 November 2013.
- Sarah Priddy, PIL: Current Members Related to Other Current or Former Members - Commons Library Standard Note, 13 September 2013.
- 'Freedom Declared: Who we are', Freedom Declared website, undated, accessed 6 November 2015
- 'Water and Safety and Drowning Prevention Register',parliament.uk, accessed 11 November 2015
- Science and Technology in Agriculture APPG,www.parliament.uk, accessed 16 November 2015
- Overseas territories APPG Register Feb 16, www.parliament.uk, accessed 18 February 2016
- Food and Health APPG Register Feb 16, www.parliament.uk, accessed 19 February 2016