The fifth season of 30 Rock, an American television comedy series on the NBC network in the United States, began airing on September 23, 2010.

[1] Beginning with episode 11, 30 Rock was moved to the 10:00 PM timeslot, but, as a consolation, was renewed earlier than the other NBC sitcoms.

[6] Season 5 continues with Liz in a relationship with Carol (Matt Damon), a man she met in the episode "I Do Do", and Jack practicing to be and then being a father.

Tina Fey portrays Liz Lemon, the head writer of a fictitious live sketch-comedy television series TGS.

[8] Donaghy's full corporate title for the majority of the season is "Head of East Coast Television and Microwave Oven Programming".

[8][12] Keith Powell plays the Harvard University alumnus and TGS staff writer James "Toofer" Spurlock.

The website's critical consensus reads, "Liz Lemon continues to fire off tart zingers in a resilient fifth season that maintains 30 Rock's streak of innovative – if somewhat inconsistent – gags, pulled off with tremendous heart.

[42][43][44] Writing for HitFix, reviewer Alan Sepinwall noted his disappointment in the fourth season and opined that the fifth had "rebounded", commenting "there have been weeks [...] where 30 Rock made me laugh longer, louder and more frequently than not only every other NBC sitcom, but every comedy on TV".

Sepinwall cited a tighter focus on its main characters, a happier Liz Lemon, smarter use of guest stars and a general improvement in quality as the reasons why the series had demonstrated such a turnaround.

Club expressed similar sentiments in regard to the fourth season, noting "the growing pains hit hard [...] the show devolved into self-parody".

However he considered that "30 Rock found its footing in its fifth season [...] it has at least aged into a show that no longer feels such a desperate need to impress.

[49] Following NBC's decision to move 30 Rock to the later time of 10:00 p.m. for the second half of the season,[50] ratings declined to beneath five million viewers per week, starting with the episode "Operation Righteous Cowboy Lightning".