Shaun Johnson is a New Zealand former professional rugby league footballer who last played as a halfback for the New Zealand Warriors in the National Rugby League and New Zealand at international level. Shaun Johnson is regarded as one of New Zealand’s greatest rugby league players, often compared to the other two classic Kiwi halves, Benji Marshall and Stacey Jones. He is the highest point scorer for both the Warriors and the New Zealand Kiwis at international level.

Johnson was born in Auckland, New Zealand. From the Whangaparaoa Peninsula, Johnson attended Whangaparaoa Primary School, as well as Orewa College, and played many sports, including basketball, rugby union and Australian rules football (representing New Zealand at Under 16 level) but made his name playing touch and Rugby League. He represented New Zealand in touch and played rugby union in his school's First XV. Johnson played for the Hibiscus Coast Raiders in the Auckland Rugby League competition before being signed by the New Zealand Warriors in 2009.

Johnson started his professional career playing for the Junior Warriors in the Toyota Cup. Johnson spent the 2009 and 2010 seasons with the Junior Warriors and played 45 matches, scoring 25 tries, 159 goals and 4 field goals to finish his Toyota Cup career with 422 points. Johnson made his NSW Cup debut for the Auckland Vulcans in 2010 and also represented the Junior Kiwis that year. His final Toyota Cup match was being part of the Junior Warriors winning the 2010 Grand Final.

Shaun Johnson made his National Rugby League debut in Round 13 against the Sydney Roosters due to an injury to Brett Seymour. In his next match in Round 14 against the Wests Tigers at Mt Smart Stadium, Johnson scored his first NRL try.  In Round 22 against the Brisbane Broncos at Suncorp Stadium, Johnson scored one of the great individual tries with an outstanding 70-metre solo try in the Warriors 20–21 loss. In the 2011 Preliminary Final against the Melbourne Storm, Johnson set up a mesmerising try for Lewis Brown to seal the game in the 76th minute to beat the Storm 20–12 at AAMI Park, The Warriors made it to the Grand Final, playing the Manly Sea Eagles. The Warriors lost to Manly 24–10 in the 2011 NRL Grand Final, however Johnson played a tremendous game and almost sparked a surprise comeback with a role in both tries and a few outstanding runs. It was the closet he would get to winning a premiership crown.

Due to Kieran Foran's hamstring injury, Johnson was selected as halfback for the New Zealand national team in the 2012 Anzac Test. In his debut test match Johnson scored an 80-metre intercept try at Eden Park in the Kiwis 20 - 12 loss. Along with Konrad Hurrell and Manu Vatuvei, Johnson was the 2012 New Zealand Warriors season top try-scorer with 12 in 22 matches. Johnson also received the Rugby League International Federation's Rookie of the Year award for 2012. Johnson played in all the Warriors' 24 matches and scored 10 tries in the 2013 NRL season.

Following the end of the season, Johnson was selected in New Zealand 2013 Rugby League World Cup squad. In the Rugby League World Cup Semi Finals against England at Wembley Stadium, after the game was locked-up at 8-all at halftime and England lead 18 - 14, with seconds to go in the game, Johnson scored the final try of the game in the 80th minute, stepping and sliding through a hole to level the score at 18-all and then converting his own try to seal the win and to cement the Kiwis' place in the World Cup final.

In February 2014, Johnson played in the Warriors inaugural NRL Auckland Nines squad and was the tournament's top point scorer with 40 points. He was named the tournament's most valuable player. By the end of the Warriors 2014 NRL season he had played in 21 matches, scoring 9 tries, kicking 63 goals and a field goal. In October 2014, Johnson was selected in New Zealand's 2014 Four Nations squad. In November, Johnson was instrumental in leading the Kiwi side to a 22 - 18 victory in the 2014 Four Nations final against Australia. He received the man of the match award after his performance, which included two assists and one try. In December 2014, Johnson won the Rugby League World Golden Boot Award for best player in the world, beating the likes of Sam Burgess, Johnathan Thurston and Greg Inglis.

Johnson was selected for New Zealand in the 2015 Anzac Test against Australia at halfback, scoring a try and kicking 3 goals in the Kiwis 26 - 12 win at Suncorp Stadium. In Round 9 against the Cronulla Sharks, Johnson scored one of the best tries of the 2015 season when he evaded 5 defenders to score the try which won the match for the Warriors 20–16 in the last minute at Remondis Stadium. In Round 20 against the Manly Sea Eagles, Johnson suffered a season-ending ankle injury while scoring a try in the Warriors 32–12 loss at Mt Smart Stadium. Johnson finished the 2015 NRL season with him playing in 18 matches, scoring 8 tries, kicking 48 goals and 2 field goals for the Warriors

In 2017 Shaun Johnson became New Zealand rugby league's greatest test points scorer as the Kiwis beat Scotland 74 - 6. Johnson's second-half try broke Matthew Ridge's record of 168 points. His 22-points total from the Rugby League World Cup match took him to 175 points. After helping to guide the Warriors back to the finals, the Warriors were bundled out by the Penrith Panthers in the first round of the 2018 NRL playoffs. In November Johnson was granted an immediate release from the final year of his contract with the New Zealand Warriors. Cronulla then announced that they had signed Johnson on a three-year deal. Johnson spoke to the media after leaving the New Zealand Warriors and took aim at his former coach Stephen Kearney saying “I’ve been at Auckland for eight years and had six coaches, The sixth coach didn't like me, so what." The talented half then left the Auckland based club in a messy affair that was handled poorly by the franchise.

Johnson made his debut for Cronulla in Round 1 of the 2019 NRL season against Newcastle and scored his first try for Cronulla in Round 5 against the Sydney Roosters at Shark Park. Johnson made a total of 18 appearances for Cronulla in his first season at the club as they finished in 7th spot on the table and qualified for the finals. Johnson played in the club's elimination final defeat by Manly at Brookvale Oval. In Round 19 of the 2020 NRL season, Johnson was taken from the field during the second half in Cronulla's match against the Sydney Roosters with a serious leg injury. Before being injured, Johnson had a league-high 23 try assists. It was later revealed that Johnson had snapped his Achilles tendon and was ruled out for the remainder of the year. On 3 June 2021, Johnson was informed by the Cronulla club that his services would not be required beyond the 2021 NRL season.

It was then announced that Johnson had resigned with NZ Warriors and the prodigal son would return home to Mt Smart in 2022. In round 5 of the 2022 NRL season, Johnson kicked the winning field goal for the New Zealand Warriors in their 25–24 golden point victory over North Queensland. In round 8, Johnson kicked a field goal in golden point extra time to win the game for New Zealand 21–20 over Canberra. Johnson made a total of 21 appearances for the New Zealand club as they finished 15th on the table.

After a few mediocre seasons, with the playing quality he started his career with far behind him, Johnson silenced all critics who said he needed to be playing in reserve grade, by starting the 2023 season strong with a 4–1 record. Johnson made major improvements to his all-around game, particularly his kicking game and playmaking ability. In Round 5, Johnson kicked a penalty goal with less than one minute remaining as the New Zealand Warriors defeated Cronulla 32–30 at Shark Park. The club at half-time trailed the match 26–6. In his post-game interview, Johnson ended the interview by saying “Up The Wahs, baby”. From that point on, the phrase Up The Wahs would end up taking New Zealand by storm.

In September, Johnson was named the 2023 Dally M Halfback of the Year and finished as the runner-up for the Dally M Medal. Johnson was awarded the Simon Mannering Medal as the Warriors' Player Of The Year. Johnson also won the Players' Player Of The Year and the One New Zealand People’s Choice award chosen by the public. He was selected in the RLPA's Team Of The Year, voted by NRL players as the best halfback in 2023. In August 2024, Johnson announced his retirement from the NRL. During round 25 the Warriors home stadium for the match was named 'Shaun Johnson Stadium'. Johnson played his final NRL match in round 26 playing against Cronulla, setting up a match winning try in the final play of his career.