| Transactions |
| Date | Team | Player | Type | OthTm | EffDate | When | Appl |
| 4/3/1979 | NYN | Kobel | Placed on Injured List | | | Before | Yes |
| 4/19/1979 | NYN | Foli | Traded away | Pit | | Before | Yes |
| 4/19/1979 | NYN | Taveras | Acquired via trade | Pit | | Before | Yes |
| 4/24/1979 | NYN | Zachry | Placed on Injured List | | 4/24/1979 | Before | Yes |
| 4/29/1979 | NYN | Kobel | Activated from Injured List | | | Before | Yes |
| 5/18/1979 | NYN | Chapman | Demoted to reserve roster | | | Before | No |
| 5/18/1979 | NYN | Ferrer | Promoted to active roster | | | Before | No |
| 5/23/1979 | NYN | Bernard | Demoted to reserve roster | | | Before | No |
| 5/23/1979 | NYN | Zachry | Activated from Injured List | | | Before | No |
| 6/1/1979 | NYN | Allen | Placed on Injured List | | 6/1/1979 | Before | No |
| 6/1/1979 | NYN | Glynn | Promoted to active roster | | | Before | No |
| 6/10/1979 | NYN | Zachry | Placed on Injured List | | 6/10/1979 | Before | No |
| 6/12/1979 | NYN | Hausman | Promoted to active roster | | | Before | No |
| 6/15/1979 | NYN | Hassler | Acquired via trade | Bos | | Before | No |
| 6/15/1979 | NYN | Scott | Demoted to reserve roster | | | Before | No |
| 6/17/1979 | NYN | Ellis | Acquired via trade | Tex | | Before | No |
| 6/17/1979 | NYN | Orosco | Demoted to reserve roster | | | Before | No |
| 6/20/1979 | NYN | Lockwood | Placed on Injured List | | 6/20/1979 | Before | No |
| 6/25/1979 | NYN | Allen | Activated from Injured List | | | Before | No |
| 7/9/1979 | NYN | Boisclair | Placed on Injured List | | 7/9/1979 | Before | No |
| 7/13/1979 | NYN | Norman | Promoted to active roster | | | Before | No |
| 7/27/1979 | NYN | Maddox | Placed on Injured List | | 7/27/1979 | Before | No |
| 7/28/1979 | NYN | Bernard | Promoted to active roster | | | Before | No |
| 7/31/1979 | NYN | Henderson | Placed on Injured List | | 7/31/1979 | Before | No |
| 8/3/1979 | NYN | Cardenal | Acquired via trade | Phi | | Before | No |
| 8/13/1979 | NYN | Montanez | Traded away | Tex | | Before | No |
| 8/18/1979 | NYN | Cardenal | Placed on Injured List | | 8/18/1979 | Before | No |
| 8/18/1979 | NYN | Maddox | Activated from Injured List | | | Before | No |
| 8/20/1979 | NYN | Burris | Acquired via trade | NYA | | Before | No |
| 8/21/1979 | NYN | Bernard | Demoted to reserve roster | | | Before | No |
| 8/21/1979 | NYN | Reardon | Promoted to active roster | | | Before | No |
| 8/30/1979 | NYN | Bernard | Promoted to active roster | | | Before | No |
| 8/30/1979 | NYN | Murray | Traded away | Mon | | Before | No |
| 9/1/1979 | NYN | Berenguer | Promoted to active roster | | | Before | No |
| 9/1/1979 | NYN | Chapman | Promoted to active roster | | | Before | No |
| 9/1/1979 | NYN | Jackson | Promoted to active roster | | | Before | No |
| 9/1/1979 | NYN | Pacella | Promoted to active roster | | | Before | No |
| 9/1/1979 | NYN | Scott | Promoted to active roster | | | Before | No |
| 9/7/1979 | NYN | Boisclair | Activated from Injured List | | | Before | No |
| 9/15/1979 | NYN | Burris | Placed on Injured List | | 9/15/1979 | Before | No |
| 9/17/1979 | NYN | Henderson | Activated from Injured List | | | Before | No |
| 9/21/1979 | NYN | Ellis | Traded away | Pit | | Before | No |
| 9/27/1979 | NYN | Cardenal | Activated from Injured List | | | Before | No |
| 9/27/1979 | NYN | Zachry | Activated from Injured List | | | Before | No |