Tigerair Taiwan is set to buy seven Airbus A320neos and lease eight more, with a total value of the deal reaching $730 million.
The delivery of the aircraft is scheduled to start in 2021.
China Airlines owns 90% of Tigerair Taiwan, with the remaining 10% owned by another affiliate, Mandarin Airlines.
Overall the airline operates 29 routes from Taiwan's Taoyuan, Kaohsiung, and Taichung to 22 destinations, many of them in Japan.