The Brit will take up the role in September, succeeding Martin Radvan, who is retiring after 32 years with the company.
Clarke (pictured, above) joined Mars in the UK in 2000 in category and sales leadership, becoming sales director in 2003. In 2007 he became general manager of Mars Ireland, then general manager for care and treats at Mars Petcare Europe in 2009, and regional president for Mars Petcare South America in 2011.
In 2015 he moved back to the UK and became chief customer officer, adding marketing to his remit the following year.
Mars was not immediately able to comment on whether they have decided on who will succeed Clarke as the company's chief marketer.
Grant F Reid, chief executive of Mars, said: "Andrew’s track record for driving ambitious change while delivering results is the fuel our business needs to thrive in an ever-changing consumer and retail landscape.
"Andrew brings great global perspective, combined with a principled approach to leadership and passion for engaging and inspiring teams."