| Episode | air date | star date |
| Spock's Brain The Enterprise Incident The Paradise Syndrome And the Children Shall Lead | 9/20/68 | 5431.4 |
| 9/27/68 | 5027.3 | |
| 10/4/68 | 4842.6 | |
| 10/11/68 | 5029.5 | |
| Is There In Truth No Beauty? Spectre of the Gun Day of the Dove For the World is Hollow and I have Touched the Sky | 10/18/68 | 5630.7 |
| 10/25/68 | 4385.3 | |
| 11//1/68 | unknown | |
| 11/8/68 | 5476.3 | |
| The Tholian Web Plato's Stepchildren Wink of an Eye The Empath | 11/15/68 | 5693.2 |
| 11/22/68 | 5784.2 | |
| 11/29/68 | 5710.5 | |
| 12/6/68 | 5121.5 | |
| Elaan of Troyius Whom Gods Destroy Let That Be Your Last Battlefield The Mark of Gideon | 12//20/68 | 4372.5 |
| 1//3/69 | 5718.3 | |
| 1/10/69 | 5730.2 | |
| 1/17/69 | 5423.4 | |
| That Which Survives The Lights of Zetar Requiem for Methuselah The Way to Eden | 1//24/69 | unknown |
| 1//31/69 | 5725.3 | |
| 2/14/69 | 5843.7 | |
| 2/21/69 | 5832.3 | |
| The Cloud Minders The Savage Curtain All Our Yesterdays Turnabout Intruder | 2/28/69 | 5818.4 |
| 3/7/69 | 5906.4 | |
| 3/14/69 | 5943.7 | |
| 6/3/69 | 5928.5 |