| | | |
| June 15, 2018 | W | Vermont Lake Monsters 1 at Tri-City ValleyCats 11 | Final |
| June 16, 2018 | L | Vermont Lake Monsters 6 at Tri-City ValleyCats 2 | Final |
| June 17, 2018 | L | Vermont Lake Monsters 4 at Tri-City ValleyCats 3 | Final |
| June 18, 2018 | W | Tri-City ValleyCats 6 at Aberdeen IronBirds 1 | Final |
| June 19, 2018 | L | Tri-City ValleyCats 1 at Aberdeen IronBirds 7 | Final |
| June 20, 2018 | W | Tri-City ValleyCats 11 at Aberdeen IronBirds 5 | Final |
| June 21, 2018 | W | Lowell Spinners 3 at Tri-City ValleyCats 9 | Final |
| June 22, 2018 | L | Lowell Spinners 11 at Tri-City ValleyCats 4 | Final |
| June 23, 2018 | W | Lowell Spinners 2 at Tri-City ValleyCats 8 | Final |
| June 24, 2018 | W | Tri-City ValleyCats 5 at Staten Island Yankees 2 | Final |
| June 25, 2018 | W | Tri-City ValleyCats 5 at Staten Island Yankees 1 | Final |
| June 26, 2018 | L | Tri-City ValleyCats 0 at Staten Island Yankees 2 | Final |
| June 28, 2018 | L | Hudson Valley Renegades 3 at Tri-City ValleyCats 1 | Final |
| June 29, 2018 | L | Hudson Valley Renegades 4 at Tri-City ValleyCats 3 | Final |
| June 30, 2018 | W | Hudson Valley Renegades 2 at Tri-City ValleyCats 9 | Final |
| July 1, 2018 | L | Tri-City ValleyCats 8 at Vermont Lake Monsters 9 | Final (11) |
| July 2, 2018 | W | Tri-City ValleyCats 3 at Vermont Lake Monsters 2 | Final |
| July 3, 2018 | L | Tri-City ValleyCats 0 at Vermont Lake Monsters 1 | Final |
| July 4, 2018 | L | Vermont Lake Monsters 6 at Tri-City ValleyCats 1 | Final |
| July 5, 2018 | W | Vermont Lake Monsters 2 at Tri-City ValleyCats 4 | Final |
| July 6, 2018 | W | Vermont Lake Monsters 1 at Tri-City ValleyCats 6 | Final |
| July 7, 2018 | W | Aberdeen IronBirds 4 at Tri-City ValleyCats 5 | Final |
| July 8, 2018 | W | Aberdeen IronBirds 3 at Tri-City ValleyCats 7 | Final |
| July 9, 2018 | W | Aberdeen IronBirds 3 at Tri-City ValleyCats 7 | Final |
| July 11, 2018 | L | Tri-City ValleyCats 6 at Williamsport Crosscutters 14 | Final |
| July 12, 2018 | W | Tri-City ValleyCats 5 at Williamsport Crosscutters 3 | Final |
| July 13, 2018 | L | Tri-City ValleyCats 1 at Williamsport Crosscutters 3 | Final |
| July 14, 2018 | W | Tri-City ValleyCats 2 at State College Spikes 0 | Final |
| July 15, 2018 | W | Tri-City ValleyCats 11 at State College Spikes 1 | Final |
| July 16, 2018 | W | Tri-City ValleyCats 2 at State College Spikes 1 | Final |
| July 17, 2018 | L | Brooklyn Cyclones 5 at Tri-City ValleyCats 0 | Final |
| July 18, 2018 | L | Brooklyn Cyclones 11 at Tri-City ValleyCats 5 | Final |
| July 19, 2018 | W | Brooklyn Cyclones 3 at Tri-City ValleyCats 7 | Final |
| July 20, 2018 | L | Tri-City ValleyCats 2 at Staten Island Yankees 7 | Final |
| July 21, 2018 | | Tri-City ValleyCats at Staten Island Yankees | Ppd. |
| July 22, 2018 | W | Tri-City ValleyCats 10 at Staten Island Yankees 1 (Game 1) | Final (7) |
| July 22, 2018 | | Tri-City ValleyCats at Staten Island Yankees (Game 2) | Susp. |
| July 24, 2018 | W | Auburn Doubledays 4 at Tri-City ValleyCats 5 | Final (10) |
| July 25, 2018 | | Auburn Doubledays at Tri-City ValleyCats | Ppd. |
| July 26, 2018 | L | Auburn Doubledays 4 at Tri-City ValleyCats 3 (Game 1) | Final (7) |
| July 26, 2018 | W | Auburn Doubledays 2 at Tri-City ValleyCats 3 (Game 2) | Final (7) |
| July 27, 2018 | | Staten Island Yankees at Tri-City ValleyCats | Ppd. |
| July 28, 2018 | | Staten Island Yankees at Tri-City ValleyCats (Game 2) | Cancelled |
| July 28, 2018 | L | Staten Island Yankees 2 at Tri-City ValleyCats 0 (Game 1) | Final (7) |
| July 29, 2018 | L | Staten Island Yankees 2 at Tri-City ValleyCats 0 (Game 1) | Final (7) |
| July 29, 2018 | W | Staten Island Yankees 1 at Tri-City ValleyCats 2 (Game 2) | Final (8) |
| July 30, 2018 | W | Tri-City ValleyCats 6 at Brooklyn Cyclones 4 | Final |
| July 31, 2018 | W | Tri-City ValleyCats 4 at Brooklyn Cyclones 3 | Final |
| August 1, 2018 | L | Tri-City ValleyCats 2 at Brooklyn Cyclones 3 | Final |
| August 2, 2018 | L | Lowell Spinners 5 at Tri-City ValleyCats 3 | Final |
| August 3, 2018 | | Lowell Spinners at Tri-City ValleyCats | Ppd. |
| August 4, 2018 | W | Lowell Spinners 3 at Tri-City ValleyCats 6 (Game 1) | Final (7) |
| August 4, 2018 | L | Lowell Spinners 2 at Tri-City ValleyCats 1 (Game 2) | Final (8) |
| August 5, 2018 | L | Tri-City ValleyCats 2 at Connecticut Tigers 6 | Final |
| August 6, 2018 | W | Tri-City ValleyCats 7 at Connecticut Tigers 4 | Final |
| August 7, 2018 | W | Tri-City ValleyCats 5 at Connecticut Tigers 2 | Final |
| August 8, 2018 | W | Hudson Valley Renegades 7 at Tri-City ValleyCats 8 | Final |
| August 9, 2018 | W | Hudson Valley Renegades 1 at Tri-City ValleyCats 6 | Final |
| August 10, 2018 | L | Hudson Valley Renegades 10 at Tri-City ValleyCats 3 | Final |
| August 11, 2018 | W | Tri-City ValleyCats 8 at Vermont Lake Monsters 5 | Final |
| August 12, 2018 | W | Tri-City ValleyCats 7 at Vermont Lake Monsters 3 | Final |
| August 15, 2018 | W | Connecticut Tigers 2 at Tri-City ValleyCats 3 | Final |
| August 16, 2018 | L | Connecticut Tigers 2 at Tri-City ValleyCats 1 | Final |
| August 17, 2018 | L | Tri-City ValleyCats 3 at Lowell Spinners 11 | Final |
| August 18, 2018 | L | Tri-City ValleyCats 2 at Lowell Spinners 9 | Final |
| August 19, 2018 | L | Tri-City ValleyCats 1 at Lowell Spinners 2 | Final |
| August 20, 2018 | W | Brooklyn Cyclones 3 at Tri-City ValleyCats 6 | Final |
| August 21, 2018 | W | Brooklyn Cyclones 2 at Tri-City ValleyCats 5 | Final |
| August 22, 2018 | W | Brooklyn Cyclones 6 at Tri-City ValleyCats 7 | Final |
| August 23, 2018 | W | Tri-City ValleyCats 5 at Hudson Valley Renegades 1 | Final |
| August 24, 2018 | L | Tri-City ValleyCats 0 at Hudson Valley Renegades 4 | Final |
| August 25, 2018 | L | Tri-City ValleyCats 6 at Hudson Valley Renegades 7 | Final (10) |
| August 26, 2018 | W | Aberdeen IronBirds 2 at Tri-City ValleyCats 4 | Final |
| August 27, 2018 | L | Aberdeen IronBirds 11 at Tri-City ValleyCats 5 | Final |
| August 28, 2018 | L | Aberdeen IronBirds 10 at Tri-City ValleyCats 1 | Final |
| August 29, 2018 | W | Tri-City ValleyCats 7 at Lowell Spinners 0 | Final |
| August 30, 2018 | W | Tri-City ValleyCats 3 at Lowell Spinners 2 | Final |
| August 31, 2018 | W | Tri-City ValleyCats 5 at Lowell Spinners 0 | Final |
| September 1, 2018 | W | Tri-City ValleyCats 6 at Vermont Lake Monsters 3 | Final |
| September 2, 2018 | L | Tri-City ValleyCats 1 at Vermont Lake Monsters 2 | Final |
| September 3, 2018 | L | Tri-City ValleyCats 6 at Vermont Lake Monsters 9 | Final |
| September 5, 2018 | W | Mahoning Valley Scrappers 6 at Tri-City ValleyCats 9 (Playoff Gm. 1) | Final |
| September 6, 2018 | W | Tri-City ValleyCats 8 at Mahoning Valley Scrappers 4 (Playoff Gm. 2) | Final |
| September 8, 2018 | W | Hudson Valley Renegades 0 at Tri-City ValleyCats 3 (Champ. Gm. 1) | Final |
| September 9, 2018 | W | Tri-City ValleyCats 4 at Hudson Valley Renegades 2 (Champ. Gm. 2) | Final (12) |
Tri-City ValleyCats Schedule
