| Date: | 13–19 May |
| Edition: | 3rd |
| Surface: | Clay |
| Location: | Lisbon, Portugal |
| Champs: |  Roberto Carballés Baena |
| Champd: |  Philipp Oswald /  Filip Polášek |
The 2019 Lisboa Belém Open was a professional tennis tournament played on clay courts. It was the third edition of the tournament which was part of the 2019 ATP Challenger Tour. It took place in Lisbon, Portugal between 13 and 19 May 2019.
| Country | Player | Rank1 | Seed | |
|---|---|---|---|---|
 France | Adrian Mannarino | 56 | 1 | |
| Spain | Roberto Carballés Baena | 91 | 2 | |
 Argentina | Guido Andreozzi | 92 | 3 | |
 Australia | Alexei Popyrin | 111 | 5 | |
| Bjorn Fratangelo | 141 | 6 | ||
| Spain | Pedro Martínez | 146 | 7 | |
| Australia | James Duckworth | 154 | 8 | |
| Marcos Giron | 157 | 9 | ||
| Argentina | Facundo Bagnis | 159 | 10 | |
 Italy | Lorenzo Giustino | 161 | 11 | |
| Italy | Alessandro Giannessi | 164 | 12 | |
| Mitchell Krueger | 170 | 13 | ||
| Spain | Enrique López Pérez | 172 | 14 | |
| João Domingues | 185 | 15 | ||
| Australia | Marc Polmans | 188 | 16 |
The following players received wildcards into the singles main draw:
The following players received entry into the singles main draw using their ITF World Tennis Ranking:
The following players received entry from the qualifying draw:
The following player received entry as a lucky loser:
See main article: 2019 Lisboa Belém Open – Singles.
Roberto Carballés Baena def. Facundo Bagnis 2–6, 7–6(7–5), 6–1.See main article: 2019 Lisboa Belém Open – Doubles.
Philipp Oswald / Filip Polášek def. Guido Andreozzi / Guillermo Durán 7–5, 6–2.