Patrick "PJ" Jacobsen (born August 7, 1993 in Montgomery, New York) is an American motorcycle racer. In 2018 he races in the Superbike World Championship aboard a Honda CBR1000RR.
He was the 2006 champion of the USGPRU 125GP Championship, and has also competed in his homeland in the USGPRU 250GP Championship and AMA Pro Daytona Sportbike Championship, plus the Spanish 125GP Championship. 2012 was a fragmented season, but included two major race wins—the British Superstock 1000 race at Donington Park and the British Supersport Championship round at Assen. For 2013 he was signed to ride in the British Superbike Championship for Tyco Suzuki. Since 2014 he participates full-time in the Supersport World Championship, initially with the Kawasaki Intermoto Ponyexpres team. Since the 2015 Portuguese round, Jacobsen switched to the CORE" Motorsport Thailand on a Honda. In August 2015, in the Malaysian round, Jacobsen became the first American to take a pole position and a win in the Supersport World Championship.