The series took an extended break from January 1, 2017 and returned on April 11, 2017.
The season concluded on May 23, 2017.
|Andy Samberg||...||Jake Peralta|
|Stephanie Beatriz||...||Rosa Diaz|
|Terry Crews||...||Terry Jeffords|
|Melissa Fumero||...||Amy Santiago|
|Joe Lo Truglio||...||Charles Boyle|
|Chelsea Peretti||...||Gina Linetti|
|Andre Braugher||...||Captain Ray Holt|
|Dirk Blocker||...||Michael Hitchcock|
|Joel McKinnon Miller||...||Norm Scully|
- The table read for the first episode occurred on July 20, 2016.
- On July 26, 2016, it was reported that Maya Rudolph would be appearing in a story arc beginning in the premiere episode playing a U.S. Marshall.
- On August 5, 2016, it was reported that Ken Marino had been cast as C.J., the Nine-Nine's new captain replacing Holt who was placed in the witness protection program at the end of Season Three.
- On August 8, 2016, it was reported that there would be a crossover episode featuring the casts of Brooklyn Nine-Nine and New Girl airing in October.
- On August 17, 2016, it was reported that Andy Samberg's Lonely Island colleague Jorma Taccone had been cast as Taylor, Captain Holt's boss at Frank's Fun Zone in Florida. Taccone previously directed Thanksgiving in Season One.
- On August 19, 2016, it was reported that Rhea Perlman had been cast as Estelle, the leader of the local power walking group in the premiere episode.
- On November 29, 2016, it was reported that Marshawn Lynch would guest star as himself for the fall finale, The Fugitive Pt. 1/The Fugitive Pt. 2.
- On December 15, 2016, weeks after a photo of Samberg and Craig Robinson surfaced, it was confirmed that Doug Judy would make his annual appearance in The Fugitive Pt. 1/The Fugitive Pt. 2.
- This is the only season till date in which Robinson appears in more than one episode.
- In the show's winter finale, Gina Linetti gets hit by a bus in the final scene. It is later announced that Chelsea Peretti is expecting her first child although Peretti has confirmed that her pregnancy and Linetti's accident is not related.
- Gina, also, is revealed to be pregnant in "The Bank Job".
- On February 7, 2017, it was reported that Nathan Fillion would guest star as an actor playing a detective who wants to help during an investigation in the set of the show he stars in, Serve and Protect. Greg Germann would also guest star as the show's executive producer. 
- On February 14, 2017, TVLine reported that Gina Gershon had signed on for a multi-episode arc playing Sergeant Melanie Hawkins, a notoriously bad-ass cop who runs the NYPD's most elite task-force.
- On March 3, 2017, it was reported that Kyle Bornheimer would reprise his role as Teddy Wells, now an NYPD auditor who's evaluating precincts to help determine which precincts should be shut down.
- On March 10, 2017, Melissa Fumero and Rick Page took to Instagram to post about the Season Four finale.
- On April 3, 2017, L. Scott Caldwell was announced to play Laverne, Captain Holt's mother.
- On April 13, 2017, it was revealed that Ryan Phillippe would play Milton, Gina's love interest although their pairing would upset Charles.
See also: List of Episodes
|1||Coral Palms Pt. 1|
|Jake and Holt remain in Florida, adjusting to their new lives under the Witness Protection Program.|
|2||Coral Palms Pt. 2|
|Jake and Holt get arrested and try to escape prison. Figgis sees the video and captures Marshall Haas. The 99 gets a new captain.|
|3||Coral Palms Pt. 3|
|Now fugitives, not only are Jake and Holt being hunted by Figgis but now also Florida Police. The 99 heads to Florida to help Jake and Holt. For disobeying their captain, the squad gets assigned to the night shift.|
|4||The Night Shift|
|Jake returns to working and tries to prove nothing has changed even when they're working the night shift. Holt tries to liven everyone's moods while in the night shift.|
|The Halloween heists continue as now there's a 3-way tie between Jake, Holt, and Amy as "The Ultimate Detective/Genius".|
|6||Monster in the Closet|
|Pimento returns and he and Rosa decide to get back where they left off, wanting to get married.|
|It's Thanksgiving in the 99 and they're celebrating at Amy's. With her father coming to visit, Jake tries to impress him. Boyle and the rest of the squad has a live turkey as their problem.|
|DC Parlov, author of The Skyfire Cycle, gets death threats and Jake and Terry try to find out who it is. Holt has a math problem.|
|CJ has a problem and Jake and Holt try to help him solve it. Terry tries to get everyone aboard the department's green initiative.|
|Jake and Charles try to locate an action figure. The rest of the squad prepares for the carolling competition, especially against the MTA.|
|11||The Fugitive Pt. 1|
|Jake and Amy make a bet where the winner keeps their apartment and the loser has to move in.|
|12||The Fugitive Pt. 2|
|Jake enlists Doug Judy's help to catch the last escaped convict. Gina and Amy teach Charles proper group text etiquette.|
|The whole squad then must band together to try to save the precinct.|
|14||Serve & Protect|
|Jake and Rosa investigate a burglary in a TV set while the others continue to deal with the audit.|
|15||The Last Ride|
|Jake and Charles go to great extremes to apprehend a local bike thief.|
|Sergeant Jeffords is stopped by a fellow police officer (guest star Desmond Harrington) while off-duty in his own neighborhood.|
|The precinct attends the annual cop-con but their fun is limited as Captain Holt asks them to be on their best behavior.|
|Amy suddenly disappears hours before her sergeant exam and Jake and Rosa try to find her.|
|Captain Holt's mother seeks the precinct's help after her house is robbed.|
|Jake and Rosa try to impress Lieutenant Melanie Hawkins while the rest of the squad try to resolve a conflict between Scully and Hitchcock.|
|21||The Bank Job|
|Jake and Rosa continue their search for a bank-robbing operation with Lieutenant Hawkins.|
|22||Crime & Punishment|
|Jake and Rosa are framed for a crime they didn't commit, it's up to the Nine-Nine to find a way to bust them out.|