The exciting forward has put pen-to-paper on a two-year deal, having made the switch from Dutch side PSV Eindhoven.
Riley, who was born in New Zealand and raised in Australia, began her professional career with A-League side Brisbane Roar.
The electric winger went on to make 20 appearances across a two-year spell with Brisbane as a teenager, before transferring to Danish side Fortuna Hjørring.
The 22-year-old netted eight goals in 63 appearances during a two-and-a-half year spell in Denmark before making a brief return to Brisbane Roar. She then went on to spend the 2023/24 campaign with Dutch side PSV.
Riley pledged her international allegiance to New Zealand in 2022 and went onto make her debut against Mexico in the September of that year, representing the Football Ferns at the 2023 FIFA Women’s World Cup in both her home nations of Australia and New Zealand.
Riley now becomes Palace’s third signing of the summer window after Katrine Veje and Shae Yañez.