1978 Toronto Blue Jays season Game log May

| Date_ | Opponent | Score | Loss | Record |
|---|---|---|---|---|
| May 14 | Mariners | Postponed (rain) Rescheduled for July 24 | Postponed (rain) Rescheduled for July 24 | Postponed (rain) Rescheduled for July 24 |
| May 15 | Angels | 10–6 | Hartzell (0–3) | 12–19 |
| May 16 | Angels | 5–4 | Aase (2–2) | 13–19 |
| May 17 | @ Orioles | Postponed (rain) Rescheduled for July 5 | Postponed (rain) Rescheduled for July 5 | Postponed (rain) Rescheduled for July 5 |
| May 18 | @ Orioles | 5–3 | Clancy (2–3) | 13–20 |
| May 19 | Yankees | 11–3 | Jefferson (2–5) | 13–21 |
| May 20 | Yankees | 10–8 | Clay (0–2) | 14–21 |
| May 21 | Yankees | 2–1 | Underwood (1–4) | 14–22 |
| May 21 | Yankees | 9–1 | Garvin (2–2) | 14–23 |
| May 22 | Red Sox | 5–4 | Clancy (2–4) | 14–24 |
| May 23 | Red Sox | 2–1 (12) | Campbell (2–4) | 15–24 |
| May 24 | Red Sox | 8–2 | Lemanczyk (1–8) | 15–25 |