Chang Kai-chen (Chinese: 張凱貞; pinyin: Zhāng Kǎizhēn; Taiwanese Mandarin: [tsáŋ kʰài tsə́n]; born January 13, 1991), also known as Kelly Chang, is a Taiwanese former professional tennis player.

Her father is Chang Chin-lai and mother is Jun Yu-mei; she has two older brothers, Yao-lun and Yao-chung (both play tennis).

Born and raised in Taiwan, an hour from Taipei, Chang splits training between Taiwan and Delray Beach, Florida (International Tennis Academy).

She qualified for the 2009 US Open, where she beat 25th seed Kaia Kanepi 6–0, 2–6, 6–2 in her first-round match.

Playing for Chinese Taipei Fed Cup team, Chang has a win–loss record of 10–8.