- This article is about the season. For the episode, click here.
|“Sensei once told me it's not the size of a ninja in a fight, it's the size of the fight in the ninja. All this training, all of these battles we've had with skeletons and Serpentine. We've persevered through so much, we can't just give up now. A ninja never admits defeat. A ninja always pick himself up when he is down. Which is exactly what Sensei Wu would want us to do right now.”|
|— Kai to the ninja in "Day of the Great Devourer"|
The first season of LEGO Ninjago: Masters of Spinjitzu, subtitled Rise of the Snakes, was preceded by the Mini-Movies and succeeded by Season 2. Each of the four original Ninja were the focus, Pythor served as the main antagonist, and the Serpentine were the villainous faction of the season. The Green Ninja was the mascot and intro character.
Since Lord Garmadon’s disappearance from the Underworld, NINJAGO Island has been at peace, but the young ninja have grown lazy. While Garmadon lurks in the shadows, waiting for the right moment to strike, the ninja meet his young son, Lloyd, who carelessly unleashes a fearsome new enemy upon NINJAGO Island – the ancient tribes of the Serpentine. The leader of the Serpentine, Pythor, hatches an evil plan to bring back the legendary, all-consuming snake, the Great Devourer.
The ninja are relaxing. But trouble is slowly brewing. . . .
- Announcer - Michael Dobson
- Acidicus - Paul Dobson
- Chokun - Michael Dobson
- Cole - Kirby Morrow
- Dr. Julien - Mark Oliver
- Ed - Colin Murdock
- Edna - Jillian Michaels
- Elderly Woman - Mark Oliver
- Falcon - Paul Dobson
- Fan #1 - Kelly Metzger
- Fan #2 - Jillian Michaels
- Fangtom - Mackenzie Gray
- Fangpyre Soldier - Brent Miller
- Fang-Suei - Michael Adamthwaite
- Father - Paul Dobson
- Garmadon - Mark Oliver
- Jay - Michael Adamthwaite
- Kai - Vincent Tong
- Kruncha - Brian Drummond
- Lloyd Garmadon - Jillian Michaels
- Lou - Kirby Morrow
- Mezmo - Michael Adamthwaite
- Mystake - Mackenzie Gray
- Mother - Kelly Metzger
- News Reporter - Paul Dobson
- Nuckal - Brian Drummond
- Nya - Kelly Metzger
- Passing Parkgoer - Michael Adamthwaite
- Postman - Michael Adamthwaite
- Pythor P. Chumsworth - Michael Dobson
- Rattla - Paul Dobson
- Skales - Ian James Corlett
- Skalidor - Michael Dobson
- Slithraa - John Novak
- Spitta - Vincent Tong
- Subway Controller #1 - Vincent Tong
- Subway Controller #2 - Michael Adamthwaite
- Tour Bus Driver - Vincent Tong
- Waitress - Kirby Morrow
- Wu - Paul Dobson
- Young Boy - Michael Adamthwaite
- Zane - Brent Miller
|Season Ep #||Series Ep #||Image||Episode name||Airdate|
|1||1||"Rise of the Snakes"||December 2, 2011 (US)|
|2||2||"Home"||December 2, 2011 (US)|
|3||3||"Snakebit"||January 25, 2012 (US)|
|4||4||"Never Trust a Snake"||February 1, 2012|
|5||5||"Can of Worms"||February 8, 2012 (US)|
|6||6||"The Snake King"||February 15, 2012 (US)|
|7||7||"Tick Tock"||February 22, 2012 (US)|
|8||8||"Once Bitten, Twice Shy"||March 7, 2012 (US)|
|9||9||"The Royal Blacksmiths"||March 14, 2012 (US)|
|10||10||"The Green Ninja"||March 21, 2012 (US)|
|11||11||"All of Nothing"||March 28, 2012 (US)|
|12||12||"The Rise of the Great Devourer"||April 4, 2012 (US)|
|13||13||"Day of the Great Devourer"||April 11, 2012 (US)|
- 9440 Venomari Shrine
- 9441 Kai's Blade Cycle
- 9442 Jay's Storm Fighter
- 9443 Rattlecopter
- 9444 Cole's Tread Assault
- 9445 Fangpyre Truck Ambush
- 9446 Destiny's Bounty
- 9447 Lasha's Bite Cycle
- 9448 Samurai Mech
- 9449 Ultra Sonic Raider
- 9450 Epic Dragon Battle
- 9455 Fangpyre Mech
- 9456 Spinner Battle Arena
- 9457 Fangpyre Wrecking Ball
- 9551 Kendo Cole
- 9552 Lloyd Garmadon
- 9553 Jay ZX
- 9554 Zane ZX
- 9555 Mezmo
- 9556 Bytar
- 9557 Lizaru
- 9558 Training Set
- 9561 Kai ZX
- 9562 Lasha
- 9563 Kendo Zane
- 9564 Snappa
- 9566 Samurai X
- 9567 Fang-Suei
- 9569 Spitta
- 9570 NRG Jay
- 9571 Fangdam
- 9572 NRG Cole
- 9573 Slithraa
- 9574 Lloyd ZX
- 9579 Starter Set
- 9590 NRG Zane
- 9591 Weapon Pack
- This is one of two consecutive seasons to contain 13 episodes, with Season 3 breaking the trend with 8 episodes.
- This is the only season in which the Golden Weapons appear in every episode.
- The collectible items featured in this season are the Golden Weapons, the Serpentine Staffs, and the Fangblades.
- This season reveals multiple things about the ninja:
- Cole mentions Clutch Powers in the ninth episode, referencing the 2010 LEGO movie, LEGO: The Adventures of Clutch Powers.
- The ninjas' four Dragons—Flame, Wisp, Shard, and Rocky—left the ninja in the third episode, only to return in the season finale, now as the Ultra Dragon—a hybrid of all four Dragons.
- The identity of the Green Ninja (being Lloyd) was accidentally revealed in February 2012, two months before the actual reveal episode, "The Green Ninja" was released due to LEGO's presence at the Toy Fair in which 9574 Lloyd ZX was revealed.
- This season has two arcs, which are Lloyd releasing the Serpentine (episodes 1-6), and the search for the Fangblades (episodes 7-13).
- The Character Encyclopedia, incorrectly refers to the pilot episodes as Season 1, and the actual Season 1 as Season 2.
- This is the first season to air over two years. The second is Season 11 which aired in 2019 and 2020 in the United States.
- There was a live stream of all the Season 1 episodes hosted by LEGO and was only available for residents of the US.
- Netflix in Australia and the UK calls this season "Rise of the Serpentine." 
- This is the only season where the four original ninja (Kai, Jay, Zane, and Cole) were the focus characters.
- Although the four original ninja were the focus ninja, Nya and Lloyd also played vital roles.
- The four original ninjas' focus was their True Potentials in episodes 7-10.
- Kai was the focus ninja in episode 10 due to his desire of becoming the Green Ninja.
- Jay was the focus ninja in episode 3 because of his relationship with his parents and episode 8 because of his relationship with Nya.
- Zane was the focus ninja in episode 2 because he had the role of being singled out and finding the Bounty and episode 7 for his discovery of being a nindroid.
- Cole was the focus ninja in episode 9 with his relationship with his father.
- Lloyd was not a ninja in the beginning, but his identity had changed several times throughout the series.
- Lloyd was an antagonist in episodes 1-4, but he became a protagonist starting from episode 5.
- Lloyd was revealed to be the Green Ninja in episode 10, which was vital to the whole story.
- Lloyd was the focus character in episode 11.
- Lloyd did not show an appearance in the main title, but the Green Ninja is seen at the beginning of each episode.
- Nya was not the focus character, but her identity of Samurai X was also a vital storyline in episodes 5 and 6.
- Wu also had some capacity in the show (like his past with Garmadon in episode 7 and Wu versus Pythor in episode 12), but the appearance of Wu was less than the six main characters.
- Pythor served as the main antagonist of the season.
- Skales served as the secondary antagonist of the season.
- Other important antagonists include Lloyd (episodes 1-4), Slithraa (episodes 1-2), Fangtom, Skalidor, Acidicus, and the Great Devourer (episode 13).
- The Serpentine were the villainous faction of the season. The Skulkin appeared in Episode 11, but not as antagonists.
- Lord Garmadon was the main antagonist of the Pilot Episodes, and appeared in episodes 8, 9, 10, 11, and 13, but not as an antagonist as he only helped the ninja rescue Lloyd and defeat the Great Devourer.