The 35-year-old will join the German Touring Car (DTM) championship while keeping his role as a reserve driver for the Alfa Romeo Racing Formula 1 team, officials announced at a press conference in Warsaw.
The announcement followed news earlier this year that Kubica had joined Alfa Romeo Racing as the Formula 1 team's reserve driver following his departure from Britain's Williams.
Polish fuel giant PKN Orlen was at the start of January announced as a new co-title sponsor for Alfa Romeo Racing starting from the 2020 season under a multi-year partnership.
PKN Orlen CEO Daniel Obajtek told reporters on Thursday: “We promised that we would be in Formula 1 and we are. But that's not all. The Poles now have their team in DTM. Robert will drive a BMW car in Polish national red-and-white colours."
Kubica said: "DTM is less well known, but it always had my great respect. The level of drivers competing in it is very high. This is a new kind of competition for me, a great challenge that I am very happy to take on. I have never competed in a vehicle with a roof on the racetrack."
Daniel Obajtek, CEO of Polish fuel giant PKN Orlen, and driver Robert Kubica during a news conference in Warsaw on Thursday. Photo: PAP/Piotr Nowak
Cars competing in the Deutsche Tourenwagen Masters (DTM) series are sometimes referred to as "Formula 1 cars with roofs," Poland’s PAP news agency reported.
It added that a total of 20 DTM races would be held this season, with the first scheduled for the weekend of April 25-26 at the Zolder circuit in Belgium, and the last in Hockenheim, Germany, on October 3-4.
Kubica in September announced this departure from British team Williams in a disappointing finale to an extraordinary Formula 1 comeback.
Kubica, the first Pole to compete in Formula 1, made his F1 debut in 2006 and claimed a total of 12 podium finishes until 2010. He won the Canadian Grand Prix with BMW Sauber in 2008 and then competed for Renault, taking three podium spots in his season with the French manufacturer.
The Pole was forced to take a break from the sport after a serious crash in a rally car in 2011.
He injured his arm, shoulder and leg. He then started a long road to recovery.
In 2017, he became a test and reserve driver for the Williams team. He returned to Formula 1 Grand Prix racing with Williams last season.