The 2018 Melbourne 400 (known for sponsorship reasons as the 2018 Coates Hire Supercars Melbourne 400) was a motor racing event for the Supercars Championship that was held on the weekend of 22 to 25 March 2018. The event was run at the Melbourne Grand Prix Circuit in Melbourne, Victoria, and marked the first running of the Melbourne 400. It was the second event of sixteen in the 2018 Supercars Championship and consisted of two races of 130 kilometres, and two races of 70 kilometers. The races were run in support of the 2018 Australian Grand Prix and marked the first time that the Supercars support races would be a points-paying round of the Supercars Championship.