| Season 4 | |
 | |
|---|---|
| Seasonal Information | |
| No. of Episodes: | 12 |
| Originally Aired: | November 8, 2009 – February 21, 2010 |
| Premiere: | "The Wedding" |
| Finale: | "Delivering Baby Mason" |
| Starring | |
| Cast: | Kris Jenner Bruce Jenner Kim Kardashian Kourtney Kardashian Khloé Kardashian Rob Kardashian Kendall Jenner Kylie Jenner |
| Season Chronology | |
| Seasons | 1 • 2 • 3 • 4 • 5 • 6 • 7 • 8 • 9 • 10 • 11 • 12 • 13 • 14 • 15 |
The fourth season of Keeping Up with the Kardashians began airing on November 8, 2009 and concluded on February 21, 2010 on E!.