Lee headlines a six-player Australian contingent at the event and at No.10 on the world amateur rankings the 20-year-old is the top player in the field this week in Singapore.

Organised by the Masters Tournament and the Royal and Ancient Golf Club of St Andrews, the Asia Pacific Amateur affords the winner a start in the following year's Masters and Open Championship should they retain amateur status.

Lee, the younger brother of LPGA Tour star Minjee Lee, is desperate to contest professional golf's two most revered major championships as an amateur.

"It would mean a lot; it's a dream," Lee told AAP from Singapore.

"We all want to play the Masters at least once in our lives, but a British Open would also be special."

Among the notable absentees at Sentosa Golf Club are amateur World No.1 Braden Thornberry and No.5 Matthew Wolff.

It means Lee will tee off on Thursday at Sentosa's New Tanjong course as the heavy favourite.

RIGHT: Lee is the highest-ranked player in the field for this week’s Asia-Pacific Amateur Championship. PHOTO: Paul Kane/Getty Images.

"There is a bit of pressure being the highest-ranked player but I've gotten the hang of that from other tournaments I've played," Lee said.

"You still have to play good golf to win and I'm determined to do that this week."

Lee led last year's Asia Pacific Amateur in New Zealand at the 36-hole mark, only to fade to a tie for third place.

"It is unfinished business for me this year. I felt like I didn't play that great in Wellington and came third," he said.

With intentions to turn professional at the end of this year, this is likely Lee's last chance to join fellow Australians Curtis Luck (2016) and Antonio Murdaca (2014) as Asia Pacific champions.

Also competing at Sentosa are Lee's countrymen and fellow world top-30 amateurs David Micheluzzi (13) and Zach Murray (30), who was the only Australian to make the round of 16 at this year's US Amateur at Pebble Beach.

The Australian contingent is rounded out by Dylan Perry (31), Shae Wools-Cobb (37) and Blake Windred (55).

Evin Priest, Australian Associated Press