Aphibarnrat turned professional in 2008 and began playing on the Asian Tour and the Japan Golf Tour in 2009. HIs first professional victory came in 2009 at the Mercedes-Benz Tour’s Singha Pattaya Open, which he won by 11 strokes, earning US$50,000. Aphibarnrat’s first Asian Tour win was at the 2011 SAIL Open.

Aphibarnrat’s first victory on the European Tour was at the Maybank Malaysian Open in March 2013. The event was co-sanctioned by the Asian Tour, thus giving him a second win on that tour. In the event, which shortened to 54 holes due to thunderstorms, Aphibarnrat defeated Edoardo Molinari by one stroke.

He won his second European Tour title at the Shenzhen International in a sudden death playoff over Li Haotong. Having led the tournament at the 54 hole stage, he trailed late in the back nine, but eagled the 17th hole and then missed a birdie putt on the 18th for the outright victory. He would go on to birdie the first extra hole to claim victory. Aphibarnrat became only the second player from Thailand, after Thongchai Jaidee, to record multiple European Tour wins.

In 2018, Aphibarnrat gained membership status on the PGA Tour for the 2018–19 season. He became the first PGA Tour member from Thailand.

In September 2021, Aphibarnrat shot rounds of 64–68 to hold the 36-hole lead at the BMW PGA Championship. A third round 74 saw him fall out of contention. He responded with a final-round 64 on Sunday to eventually finish in a tie for second place, one shot behind Billy Horschel.

Aphibarnrat is sometimes referred to as “Asia’s John Daly”, a comparison of his physique to the similarly large body type of two-time major championship winner John Daly.