Július Kubinský (born November 1923 in Prievidza, died 30 April 2008) was a Slovak-born Czech Formula 1 constructor from Brno.
Born in what is now in Slovakia, Kubinský was an avid fan of cars and planes and he was also an amateur pilot. After the end of World War II Kubinský attempted to manufacture sportscars using the German military car KdF 82 in Bratislava. He then moved to Brno in 1946 and started working for the Karosa factory. There he eventually designed the JK 2500 sportscar with a Tatra T603 engine (the only JK 2500 ever made). He drove the car for about 13 years before selling it. Among other cars, he also designed the JK Sport using the Alfa Romeo and BMW engines.
He attempted to enter the 1949 Czechoslovakian Grand Prix with a Lancia-powered car he constructed and driver Karel Vlašín behind the wheel. However Vlašín had to withdraw from the race due to damage sustained in a collision with a truck.
In 1955, he bought two Formula 1 cars, an OSCA and a Bentley-OSCA from 1953. He modified them and rebadged them as JK Mono-Tatra. The OSCA-based car was entered by him for Jaroslav Vlcek in the 1955 Soviet Grand Prix, while the Bentley-based car was purchased by the State Committee for Sports and Body Culture of USSR and entered for the same race. In the race itself, Jaroslav Vlcek finished 12th, and the other JK Mono-Tatra that was entered by the State Committee for Sports and Body Culture of USSR finished in 11th place. In 1956, Kubinsky modified another ex-OSCA design, in this case, the OSCA from 1954, and renamed the chassis JK Mono IV, and the engine Wartburg 310, signing DDR F3 champion Willy Lehmann to drive the car, with the JK Mono-Tatra combo being entered again, with Jaroslav Vlcek returning in the wheel.
He has a son called Petr, to whom Julius gifted a version of the Velorex for Petr's 15th birthday.