Damash Jahanbakhsh played most of his youth in
Rasht and Persian
Qazvin before joining the youth academy of
Damash Tehran in 2008. Jahanbaksh started his career in
Tehran with
Damash Tehran, an affiliate of Damash Gilan in the
2nd Division. In 2011, Jahanbakhsh returned to Gilan and at the age of 17. In 2011, Jahanbakhsh played his first game for
Damash Gilan in the
Iran Pro League against
Mes as one of Damash's youngest ever players. Jahanbakhsh scored his first goal on 15 January 2012 in a 1–0 victory against
Fajr. In 42 league appearances with Damash, he scored 10 goals.
NEC 2013–14 season Though he was expected to join Iran's giants,
Persepolis, On 26 May 2013, Jahanbakhsh reached a verbal agreement with Dutch Eredivisie outfit
NEC for a three-year deal. This deal was subject to a medical examination and obtaining a visa and work permit. He officially joined the club on 1 July 2013. He made his debut as a substitute in a league match against
Groningen on 3 August 2013. He scored his first goal in an 8–0 win over
Harkemase Boys in the
KNVB Cup. On 1 December 2013, Jahanbakhsh scored two goals and assisted the other in a 3–2 league match win over
AZ Alkmaar. On 22 December, he scored and assisted at
FC Groningen while providing a secondary assist on 15 February 2014 against RKC Waalwijk. On 22 March, when NEC were down 2–0 at halftime, Jahanbakhsh came on as a substitute after the half and provided an assist to
Michael Higdon in their 2–2 draw at
Heerenveen. On the final day of the
2013–14 season, Jahanbakhsh scored two late goals against
Ajax to save NEC from automatic relegation, instead securing a relegation playoff spot. Jahanbakhsh was originally voted the Eredivisie's greatest talent of the season before becoming runner-up to
Memphis Depay.
2014–15 season On the opening day of the
2014–15 Jupiler League, Jahanbakhsh scored a goal in a 3–1 win against
FC Eindhoven. On 29 August, he scored two goals and provided two assists in a 4–1 win at
Helmond Sport. On 20 September, he scored against
FC Emmen to help bring NEC to the top of the league table. Three days later, on 23 September, AJ scored a
free kick in extra time and converted a penalty in their win against
Ajax II at
Amsterdam during the second round of the
2014–15 Dutch Cup. On 3 October, he scored a goal and provided an assist in a 2–1 win against
Almere City to send NEC to the
Eredivisie play-offs as quarter-season league champions. On 17 October 2014, Jahanbakhsh was named the Best Player of the First Period of the
2014–15 Jupiler League. On 28 November, he opened the scoring with a
volley and provided two assists in a 5–1 win over
Jong Twente. On 1 February 2015, in his first game upon his return from the
2015 AFC Asian Cup, he scored a
bicycle kick and was named
man of the match in the 3–1 win over
Helmond Sport. On 13 February, he scored a goal and provided two assists in a 3–2 win over
FC Emmen with another goal against
Achilles '29 days later to bring his tally to 4 goals in 5 consecutive matches after the Asian Cup. At the end of the season, Jahanbakhsh was selected by fans as NEC's player of the season. On 12 May 2015 Jahanbakhsh was voted as the Eerste Divisie's best player for the 2014–15 season, with twelve goals and eighteen assists in the league.
AZ 2015–16 season On 3 August 2015, Jahanbakhsh signed a five–year contract with Dutch club
AZ Alkmaar. He was given number nine as his jersey number, and made his
Eredivisie debut for AZ on 12 September 2015 in a 3–1 win over
De Graafschap. Jahanbakhsh made his
UEFA Europa League debut in a 2–1
group stage win over
Athletic Bilbao on 1 October 2015. Jahanbakhsh recorded his first assist for AZ on 21 November 2015 in a 3–1 victory against
Heerenveen. Jahanbakhsh scored his first goal for AZ on 30 January 2016 in a match against his former club
NEC. He scored his second goal of the season and also recorded his fourth assist on 13 February 2016 in a 6–3 victory over
Heracles Almelo.
2016–17 season In June 2016 Jahanbakhsh switched from number 9 to number 7 for the upcoming 2016–17 season. On 2 July 2016, in AZ's first preseason match, Jahanbakhsh recorded a goal and an assist in his team's 5–1 victory. On 28 August he scored his first goal of the season against
FC Utrecht. The match was ended 2-1 which Jahanbakhsh scored the winning goal. On 13 January 2017, Jahanbakhsh scored a brace and recorded an assist, as well as being named man of the match in a 3–1 victory against
Go Ahead Eagles. On 21 August 2016, he scored his first goal of the season in a 2–1 win over
Utrecht. On 16 February 2017, he scored his first ever
European goal in a 4–1 loss to
Lyon in Round of 32 of the
Europa League. Jahanbakhsh was named the best winger of the 2016–17 season in the Dutch League.
2017–18 season Jahanbakhsh scored a hat trick and recorded an assist on 18 April 2018 against Vitesse in the
2017–18 Eredivisie. Jahanbakhsh scored another hat trick on the last match day to become the leading goal scorer of the Eredivisie season with 21 goals, and also finished joint third with 12 assists.
Brighton & Hove Albion 2018–19 season On 25 July 2018, Jahanbakhsh transferred to
Premier League side
Brighton & Hove Albion for an undisclosed club record fee, signing a five-year contract. He announced on his
Instagram that he will wear number 16, the same number he used to wear in his first season at
NEC. On 11 August 2018, Jahanbakhsh made his debut for Brighton as a substitute in the club's opening match of the
Premier League season against
Watford. Even though he played 25 matches in the season due to injuries and poor performance he amounted no goals and no assists.
2019–20 season With the managerial change at Brighton with
Graham Potter replacing
Chris Hughton, Jahanbakhsh rarely found himself in the match squad until 8 December 2019 when he came on as a substitute in a match against
Wolverhampton. On 28 December 2019, he scored his first goal for the club on his first start against
Bournemouth. Jahanbakhsh was overcome with emotion and was seen crying after scoring his first ever goal for his club. On 1 January 2020, he scored an equalising bicycle kick goal for Brighton against
Chelsea. The goal against Chelsea was later voted by people as the
Premier League Goal of the Month for January, in which Jahanbakhsh described it as the best goal he has ever scored.
2020–21 season Jahanbakhsh came on as a sub in the
Brighton's opening day of the season in a 3–1 home loss against Chelsea in the league. He scored a cracker in the next game, a 4–0 home thrashing over
Portsmouth in the
EFL Cup on 17 September. He scored again 6 days later again coming in the EFL Cup, this time a 2–0 away win over
Preston. Jahanbakhsh started in Brighton's 3–2 home victory over champions
Manchester City on 18 May 2021, with fans returning to football. Brighton came back from 2–0 down to secure their first win over
The Sky Blues since 1989.
Feyenoord On 17 July 2021,
Feyenoord announced that Jahanbakhsh had joined the club on a 3-year contract with an option for a fourth year. He made his debut for Feyenoord on 29 July in the second leg of the
UEFA Europa Conference League tie against
FC Drita where he started the match but later substituted in the 3–2 home victory, with Feyenoord also going through 3–2 on aggregate. He scored his first two goals for the club on 12 August, scoring Feyenoord's first two goals in a 3–0 win against
FC Luzern in the
third qualifying round of the 2021–22 UEFA Europa Conference League. Jahanbakhsh made his league debut for the
Rotterdam side on 22 August starting in the 2–0 home victory over
Go Ahead Eagles.
SC Heerenveen On 6 November 2024, Jahanbakhsh signed a contract with Dutch Eredivisie club SC Heerenveen until the end of the season.
FCV Dender On 4 November 2025, after being a free agent for the start of the season, Jahanbakhsh joined a winless
FCV Dender EH on a one year deal with an option for an additional year. He made his debut against
Zulte Waregem on November 7th, coming off the bench in the 69th minute. ==International career==