| Date: | 18–24 March |
| Edition: | 3rd |
| Surface: | Hard |
| Location: | Zhangjiagang, China |
| Champs: |  Marc Polmans |
| Champd: | Max Purcell / Luke Saville |
| After Year: | 2023 |
The 2019 International Challenger Zhangjiagang was a professional tennis tournament played on hard courts. It was the third edition of the tournament which was part of the 2019 ATP Challenger Tour. It took place in Zhangjiagang, China between 18 and 24 March 2019.
| Country | Player | Rank1 | Seed | |
|---|---|---|---|---|
 Canada | Brayden Schnur | 106 | 1 | |
| Australia | James Duckworth | 166 | 2 | |
 Korea, Republic of | Kwon Soon-woo | 170 | 3 | |
 Japan | Hiroki Moriya | 174 | 4 | |
| Japan | Yūichi Sugita | 176 | 5 | |
 Italy | Lorenzo Giustino | 189 | 6 | |
| Blaž Rola | 199 | 7 | ||
 China | Zhang Ze | 201 | 8 | |
| Japan | Go Soeda | 205 | 9 | |
| Australia | Marc Polmans | 210 | 10 | |
| Viktor Galović | 213 | 11 | ||
 Egypt | Mohamed Safwat | 216 | 12 | |
| Italy | Stefano Napolitano | 229 | 13 | |
| Canada | Filip Peliwo | 233 | 14 | |
 France | Mathias Bourgue | 239 | 15 | |
| Korea, Republic of | ||||
 Belarus | Uladzimir Ignatik | 245 | 17 |
The following players received wildcards into the singles main draw:
Gao Xin He Yecong Hua Runhao Xia Zihao Zhang ZhizhenThe following player received entry into the singles main draw using a protected ranking:
The following player received entry into the singles main draw as an alternate:
Makoto OchiThe following players received entry into the singles main draw using their ITF World Tennis Ranking:
Baptiste Crepatte
Ivan Gakhov Kim Cheong-eui Karim-Mohamed MaamounThe following players received entry from the qualifying draw:
See main article: 2019 International Challenger Zhangjiagang – Singles.
Marc Polmans def. Lorenzo Giustino 6–4, 4–6, 7–6(7–4).See main article: 2019 International Challenger Zhangjiagang – Doubles.
Max Purcell / Luke Saville def. 
Sriram Balaji / 
Hans Hach Verdugo 6–2, 7–6(7–5).
