BERLIN, May 3 (Reuters) - Porsche AG's supervisory board has appointed Michael Steiner as new head of research and development, replacing Wolfgang Hatz who will leave the sports-car maker at his own request.

Steiner, currently head of quality management, will succeed Hatz immediately, Porsche said on Tuesday.

Hatz, who held a senior position at parent Volkswagen before switching to Porsche in 2011, was suspended last September after VW's diesel emissions test-cheating scandal broke.

(Reporting by Andreas Cremer; Editing by Maria Sheahan) ((Andreas.Cremer@thomsonreuters.com; +49-30-2888-5084; Reuters Messaging: andreas.cremer.thomsonreuters.com@reuters.net))