UFC Fight Night: Smith vs. Spann is a mixed martial arts event produced by the Ultimate Fighting Championship that took place on September 18, 2021 at the UFC APEX, Las Vegas United States.

Main Card
| Weight Class | Fight | Method | Round | Results |
| Light Heavyweight | Anthony Smith vs. Ryan Spann | Submission | R1 (03:47) | Anthony Smith def. Ryan Spann |
| Light Heavyweight | Ion Cuțelaba vs. Devin Clark | Decision | R3 (05:00) | Ion Cuțelaba def. Devin Clark |
| Women Flyweight | Ariane Lipski vs. Mandy Böhm | Decision | R3 (05:00) | Ariane Lipski def. Mandy Böhm |
| Lightweight | Arman Tsarukyan vs. Christos Giagos | KO/TKO | R1 (02:09) | Arman Tsarukyan def. Christos Giagos |
| Bantamweight | Nathan Maness vs. Tony Gravely | KO/TKO | R2 (02:10) | Nathan Maness def. Tony Gravely |
| Middleweight | Joaquin Buckley vs. Antonio Arroyo | KO/TKO | R3 (02:26) | Joaquin Buckley def. Antonio Arroyo |
Preliminary Card
| Weight Class | Fight | Method | Round | Results |
| Light Heavyweight | Mike Rodriguez vs. Tafon Nchukwi | Decision | R3 (05:00) | Tafon Nchukwi def. Mike Rodriguez |
| Women Bantamweight | Pannie Kianzad vs. Raquel Pennington | Decision | R3 (05:00) | Raquel Pennington def. Pannie Kianzad |
| Lightweight | Zhu Rong vs. Brandon Jenkins | KO/TKO | R3 (04:35) | Zhu Rong def. Brandon Jenkins |
| Bantamweight | Montel Jackson vs. JP Buys | Decision | R3 (05:00) | Montel Jackson def. JP Buys |
| Women Flyweight | Erin Blanchfield vs. Sarah Alpar | Decision | R3 (05:00) | Erin Blanchfield def. Sarah Alpar |
| Welterweight | Impa Kasanganay vs. Carlston Harris | KO/TKO | R1 (02:38) | Carlston Harris def. Impa Kasanganay |
| Bantamweight | Gustavo Lopez vs. Heili Alateng | Decision | R3 (05:00) | Draw |
| Women Flyweight | Emily Whitmire vs. Hannah Goldy | Submission | R1 (04:17) | Hannah Goldy def. Emily Whitmire |