The agency won the business after a competitive pitch against The Red Brick Road, Anomaly and Amp London. A review of the business was launched in June and was handled by the intermediary Will Hamilton Associates.
PAA will handle the hotel group's advertising, digital and direct marketing across major European markets, including the UK.
The agency will launch an integrated campaign across brands including Ritz-Carlton, JW Marriott, Marriott Hotels & Resorts and Renaissance Hotels immediately.
Marriott's European division did not previously have a retained ad agency, but Marriott International, the brand's global division, works with Mcgarrybowen and Team One in the US. Marriott's global media planning and buying is handled by MEC.
The appointment comes midway through the hotel group's five-year plan to double its portfolio across Europe by 2015. This will see an increase from 40,000 rooms to 80,000 rooms across 174 hotels.
Last year, Mcgarrybowen launched a £6 million global advertising campaign for Marriott featuring six watercolour illustrations that feature within Marriott Hotels & Resorts in London, Beijing, Aruba and Pune.Follow @SaraKimberley