Kubica began karting in Poland at the age of ten, winning six titles in three years before moving to Italy, where in 1998 he became the first foreigner to win the International Italian Junior Karting Championship. He also won the Junior Monaco Kart Cup, the Andrea Margutti Trophy, and the Elf Masters before finishing fourth in both the European and World Karting Championships in 2000.
In single-seaters he won four races in the Italian Formula Renault 2.0 in 2002, then progressed through the Formula 3 Euro Series — entering his debut wearing a plastic brace over a broken arm — before winning the World Series by Renault with Epsilon Euskadi in 2005, earning Formula One tests with Renault.
Kubica joined BMW Sauber as official reserve driver in 2006. When teammate Jacques Villeneuve was deemed unfit after the German Grand Prix, Kubica replaced him at the Hungarian Grand Prix, qualifying ninth and finishing seventh before being disqualified for an underweight car. At the Italian Grand Prix in his third race, he finished third, becoming the first Polish driver to stand on a Formula One podium and the first driver to podium within his first three starts since Alexander Wurz in 1997.
In 2007, Kubica suffered a high-speed crash at the Canadian Grand Prix approaching the hairpin, with his car measured at 300.13 km/h when it struck the barrier at a 75-degree angle, subjecting him to a peak of 75 G. He was not seriously injured and returned to racing.
The 2008 season brought his breakthrough victory. At the Canadian Grand Prix on 8 June, Kubica started second and passed race leader Lewis Hamilton during pitstops after a faster BMW Sauber pit cycle. Hamilton then missed a red light at the pit exit and collided with Kimi Raikkonen's Ferrari, eliminating both from the race. Kubica managed his two-stop strategy to beat teammate Nick Heidfeld and take victory, also holding the lead in the Drivers' Championship at that stage. He finished the season fourth overall, with additional podiums at Valencia and Monza. BMW announced in July 2009 that it would leave Formula One at season's end, making Kubica a free agent.
Kubica joined Renault for 2010 and delivered one of the most consistently rated seasons of his career. He finished on the podium three times — Australia, Monaco, and Belgium — with Formula One journalist Mark Hughes describing him as "arguably the best driver" based on his performances at skill-demanding circuits including Monaco, Spa, and Suzuka.
He was retained for 2011, but on 6 February of that year, during the Ronde di Andora rally in Italy, his Skoda Fabia Super 2000 left the road at high speed and struck a crash barrier near the church of San Sebastiano in Testico. The barrier penetrated the car's cockpit while leaving his co-driver unscathed. Kubica was trapped for more than an hour before rescue workers freed him. He was airlifted to hospital in Pietra Ligure, where surgeons confirmed a partial amputation of his right forearm and compound fractures to his right elbow, shoulder, and leg. A seven-hour operation by two teams of surgeons followed, with two further procedures over subsequent days. Kubica had previously signed a pre-contract to drive for Ferrari in 2012; those plans were ended by the accident.
After re-breaking his right leg on ice in January 2012, Kubica returned to competition in September 2012 by winning a minor Italian rally. Top Gear named him one of its Men of the Year 2012 for the comeback.
In 2013, driving for Citroen in WRC2, he won five rallies — including the Acropolis, Rally d'Italia, Rallye Deutschland, and Rally RACC Catalunya — and clinched the inaugural WRC-2 Championship title. He moved to the main WRC class for 2014 with RK M-Sport backed by Lotos, led the Monte Carlo Rally's opening stages before retiring on day two, and finished the season with a best result of sixth in Argentina. He also won the non-championship Monza Rally Show ahead of Valentino Rossi. Funding limitations restricted his 2016 WRC programme to just the Monte Carlo Rally.
After testing a 2012 Renault Formula One car at Circuit Ricardo Tormo in June 2017 — his first F1 appearance since 2010 — Kubica completed further tests with Renault at the Hungaroring and with Williams at Silverstone and the Hungaroring. Williams announced him as reserve driver for 2018, and on 22 November 2018, confirmed him as a full-time race driver for 2019, partnering 2018 Formula 2 champion George Russell.
The 2019 season proved difficult. Williams' FW42 was the slowest car in the field. Kubica scored his sole point of the season at the German Grand Prix after penalties promoted him to tenth, setting a record for the longest gap between consecutive points finishes. He ended the season 19th in the championship with one point and departed Williams.
He joined Alfa Romeo as reserve and test driver for 2020, then substituted for Kimi Raikkonen — who tested positive for COVID-19 — at the 2021 Dutch and Italian Grands Prix, finishing 15th and 14th respectively. He remained with Alfa Romeo in reserve capacity through 2022 before departing when sponsor Orlen moved to Scuderia AlphaTauri.
In 2021, Kubica drove with Orlen Team WRT in the European Le Mans Series, winning three rounds and the LMP2 title, and also made two late-season WEC appearances with High Class Racing in Bahrain, contributing to two ProAm podiums. After a 2022 WEC season with Prema Orlen Team — covering the 24 Hours of Le Mans and the Sebring 1000 Miles — he returned to WRT for 2023 and secured the WEC LMP2 class championship.
For 2024, Kubica stepped up to the Hypercar class with AF Corse, driving the No. 83 Ferrari 499P alongside Ye Yifei and Robert Shwartzman. He won the Lone Star Le Mans race in September 2024, becoming only the third driver in history to win both a Formula One race and a WEC race, after Fernando Alonso and Mark Webber.
In 2025, he took overall victory at the 24 Hours of Le Mans with Phil Hanson and Ye Yifei, the first Polish driver to win the race outright. At the season-ending 8 Hours of Bahrain he finished second overall in the same car.
Kubica's career spans three distinct acts: a Formula One debut that placed him among the fastest drivers of his era, a near-fatal accident and recovery that tested the limits of what elite athletes can endure, and a late-career resurgence in endurance racing that added a Le Mans victory to his Canadian Grand Prix win. He remains the only Polish driver to race in Formula One and the only Polish driver to win the 24 Hours of Le Mans overall.