Atthaya Thitikul (Thai: อาฒยา ฐิติกุล, RTGS: Atthaya Thitikun, pronounced [ʔàːt.tʰā.jāː tʰì(ʔ).tì(ʔ).kūn]; born 20 February 2003), also Jeeno Thitikul, is a Thai professional golfer who plays on the U.S.-based LPGA Tour and the Ladies European Tour.

[1] She was the number one ranked women's amateur golfer in the world for a total of 12 weeks, rising to the top on two occasions, the first time on 26 June 2019.

In November 2024, she won the CME Group Tour Championship and earned a prize of $4 million.

[1][12] Thitikul honed her skills and graduated from Sarasas Witaed Nakhonpathom School in Nakhon Pathom.

[17][18] She had earned her place in the field when she finished runner-up in the Thailand Amateur Open the previous August when she was just 13 years and 6 months old.

She held the record until April 2023, when Louise Uma Landgraf won the Terre Blanche Ladies Open aged 14 years, 2 months and 18 days.

Her amateur status meant that she could not claim the first prize of 45,000 euros for winning but it gave her the entries into both the Women's British Open and the Evian Championship in France.

At the HSBC event, she was the joint youngest starter of the championship at 15 years and 9 months, the exact same age at which Singapore's Amanda Tan competed in 2014.

[28][29] At the ANA Inspiration in March, she finished in a tie for 30th place and earned low amateur honours.

[32] On 15 September, she broke the course record at World Junior Girls Championship on Camelot Golf and Country Club in Ottawa with a score of 12-under-par 60 in the final round to win the title by 2 strokes.

[37] In August, she won the back-to-back Smyth Salver, low amateur honour, at the Women's British Open after finishing in a tie for 29th place at Woburn.

[47] This win made her eligible to play in European major tournaments, the Evian Championship and the British Open in 2021.

[49] On 15 August, she achieved her seventh consecutive top-five place on a Ladies European Tour event by finishing tied for second in the Trust Golf Women's Scottish Open at Dumbarnie Links.

[56] Thitikul won the Ladies European Tour Order of Merit and Rookie of the Year titles, following her two wins, three runner-ups, and nine additional top-ten finishes.

[60] In early March, Thitikul tied for fourth place at the HSBC Women's World Championship in Singapore.

[69][70] Notably, she became the second-youngest golfer to reach this milestone, after Lydia Ko, who achieved the feat at 17 years and nine months old in February 2015.

Thitikul averaged 69.53 strokes over 75 rounds without winning a single tournament, marking the first time in 70 years that the Vare Trophy went to a non-winner.

[73] In December, Thitikul played on the Ladies Asian Tour, where she secured a 7-stroke victory at the Simone Asia Pacific Cup, claiming the $110,000 first prize.

[75] On 19 November 2024, she secured first place in the Aon Risk Reward Challenge, being awarded its $1 million prize.