| Champ: | Marin Čilić |
| Runner: |  Novak Djokovic |
| Score: | 5–7, 7–6(7–4), 6–3 |
| Draw: | 32 |
| Seeds: | 8 |
| Type: | queensclubtennistournament |
| Before Name: | Aegon Championships – Singles |
See main article: article and 2018 Queen's Club Championships.
Marin Čilić defeated Novak Djokovic in the final, 5–7, 7–6(7–4), 6–3 to win the singles tennis title at the 2018 Queen's Club Championships. He saved a championship point in the second set. This was Djokovic's first ATP Tour final in almost a year, and Čilić's second victory over Djokovic in their 16 matches played.
Feliciano López was the defending champion, but lost in the quarterfinals to Nick Kyrgios.