Season Four of My Three Sons premiered on September 19, 1963.
 Episodes
| # | # | Title |  |  | Airdate |  |  |  | 
| 112 | 1 | Almost the Sound of Music |  |  | September 19, 1963 |  |  |  | 
| 113 | 2 | Scotch Broth |  |  | September 26, 1963 |  |  |  | 
| 114 | 3 | Didya Ever Have One of Those Days? |  |  | October 3, 1963 |  |  |  | 
| 115 | 4 | Dear Robbie |  |  | October 10, 1963 |  |  |  | 
| 116 | 5 | A Car of His Own |  |  | October 17, 1963 |  |  |  | 
| 117 | 6 | How Do You Know? |  |  | October 24, 1963 |  |  |  | 
| 118 | 7 | My Friend Ernie |  |  | October 31, 1963 |  |  |  | 
| 119 | 8 | The End of the You-Know-What |  |  | November 7, 1963 |  |  |  | 
| 120 | 9 | The Toupee |  |  | November 14, 1963 |  |  |  | 
| 121 | 10 | The Ever-Popular Robbie Douglas |  |  | November 21, 1963 |  |  |  | 
| 122 | 11 | The Proposals |  |  | November 28, 1963 |  |  |  | 
| 123 | 12 | Steve and the Viking |  |  | December 5, 1963 |  |  |  | 
| 124 | 13 | Par for the Course |  |  | December 12, 1963 |  |  |  | 
| 125 | 14 | Windfall |  |  | December 19, 1963 |  |  |  | 
| 126 | 15 | Top Secret |  |  | December 26, 1963 |  |  |  | 
| 127 | 16 | Will Success Spoil Chip Douglas? |  |  | January 2, 1964 |  |  |  | 
| 128 | 17 | Second Chorus |  |  | January 9, 1964 |  |  |  | 
| 129 | 18 | Never Look Back |  |  | January 16, 1964 |  |  |  | 
| 130 | 19 | Marriage by Proxy |  |  | January 23, 1964 |  |  |  | 
| 131 | 20 | The Chaperone |  |  | January 30, 1964 |  |  |  | 
| 132 | 21 | My Fair Chinese Lady |  |  | February 6, 1964 |  |  |  | 
| 133 | 22 | House for Sale |  |  | February 13, 1964 |  |  |  | 
| 134 | 23 | Stone Frog |  |  | February 20, 1964 |  |  |  | 
| 135 | 24 | Stage Door Bub |  |  | February 27, 1964 |  |  |  | 
| 136 | 25 | Fish Gotta Swim, Birds Gotta Fly |  |  | March 5, 1964 |  |  |  | 
| 137 | 26 | Cherry Blossoms in Bryant Park |  |  | March 12, 1964 |  |  |  | 
| 138 | 27 | What's the Princess Really Like? |  |  | March 19, 1964 |  |  |  | 
| 139 | 28 | The People's House |  |  | March 26, 1964 |  |  |  | 
| 140 | 29 | The Tree |  |  | April 2, 1964 |  |  |  | 
| 141 | 30 | The Substitute Teacher |  |  | April 9, 1964 |  |  |  | 
| 142 | 31 | Mike Wears the Pants |  |  | April 16, 1964 |  |  |  | 
| 143 | 32 | The Guys and the Dolls |  |  | April 23, 1964 |  |  |  | 
| 144 | 33 | The Ballad of Lissa Stratmeyer |  |  | April 30, 1964 |  |  |  | 
| 145 | 34 | Tramp Goes to Hollywood |  |  | May 7, 1964 |  |  |  | 
| 146 | 35 | Adventure in New York |  |  | May 14, 1964 |  |  |  | 
| 147 | 36 | Huckleberry Douglas |  |  | May 21, 1964 |  |  |  | 
| 148 | 37 | Guest in the House |  |  | May 28, 1964 |  |  |  |