Ski Cross (also known as Skiercross or Skier-X) is a type of skiing competition. It is based on the snowboarding discipline of boardercross. Despite it being a timed racing event, it is often considered part of freestyle skiing because it incorporates terrain features traditionally found in freestyle.

In a time trial or qualification round, every competitor skis down the course, which is built to encompass both naturally occurring terrain and artificial features like jumps, rollers, banks ? whatever the course builder can imagine. After the time trial, the fastest 32 skiers (fastest 16 if not 32 competitors) compete in a knockout (KO)-style series in rounds of four. A group of four skiers start simultaneously and attempt to reach the end of the course. The first two to cross the finish line will advance to the next round. At the end, the final and small final rounds determine 1st to 4th and 5th to 8th places, respectively.

Competitors are not allowed to pull or push each other during the KO finals. Any intentional contact to the other competitors will be penalized by disqualification or exclusion from the next race.

The International Ski Federation (FIS) (International Ski Federation)s FIS Freestyle Skiing World Cup has recently added Ski Cross competitions to its calendar in addition to moguls (mogul (skiing)) and aerials.

The International Olympic Committee decided on November 28, 2006, to include Ski Cross in the programme of the 2010 Winter Olympics at Vancouver. Ashleigh McIvor of Whistler, BC, raced to an olympic gold medal in womens Ski Cross on February 23, 2010 during the 2010 winter Olympics in British Columbia Canada.

The concept for Ski Cross originated from Jim "Too Tall" Essick of Recreational Sports Marketing. In the late 1980s, Jim came up with a concept that would make ski racing more exciting for spectators. Using a format similar to Nascar and Motocross, Jim envisioned placing four skiers on a course simultaneously, letting them race head-to-head on course that combined jumps and gates. Jim and his business partner, Diana Schulz, marketed the event as "Quattro Racing", trying to sell the concept to Audi, as a promotional vehicle for the Audi Quattro. The concept was also pitched to Swatch Watch, who became interested in the format for snowboarding. That sport is now known as Boarder Cross.