Shreyas Santosh Iyer (শ্রেয়াস সন্তোষ আইয়ার) is an Indian international cricketer who plays for the Indian team as a right-handed middle-order batter. He also plays for Mumbai in domestic cricket and captains the Punjab Kings in the Indian Premier League. He was a part of the Indian team that won the 2025 Champions Trophy.

Iyer was born on 6 December 1994 in Chembur, Bombay (now Mumbai). His father, Santosh Iyer, is a Tamilian, and his mother, Rohini Iyer, is a Tuluva. His ancestors are from Thrissur, Kerala. He was educated at Don Bosco High School, Matunga and at Ramniranjan Anandilal Podar College of Commerce and Economics, Mumbai.

In 2014, Iyer represented the Trent Bridge Cricket Team. During a trip to the UK, he played three matches, scoring 297 runs and averaging 99 runs per game. He set a new team record with a highest score of 171.

Iyer made his List A debut for Mumbai in November 2014, playing in the 2014–15 Vijay Hazare Trophy. He scored 273 runs in that tournament at an average of 54.60. Iyer made his first-class cricket debut in December 2014 during the 2014–15 Ranji Trophy. He scored a total of 809 runs at an average of 50.56 in his debut Ranji season, including two centuries and six fifties. He was 7th highest scorer of the 2014–15 Ranji Trophy.

In March 2017, Iyer was included in India's Test squad as a replacement for Virat Kohli before the fourth Test against Australia. He served as a substitute fielder in the fourth test and successfully ran out Steve O'Keefe for 8.

In October 2017, Iyer was named in India's Twenty20 International (T20I) squad for their series against New Zealand. He made his T20I debut for India against New Zealand on 1 November 2017, but he did not bat. In November 2017, Iyer was named in India's One Day International (ODI) squad for their series against Sri Lanka. He made his ODI debut for India against Sri Lanka on 10 December 2017. He scored 88 from 70 balls in the 2nd ODI against Sri Lanka at Mohali.

On 18 December 2019, in the second ODI against the West Indies, Iyer scored 31 runs in one over, the most scored by a batsman for India in a single over in ODIs.