A pair of 13-year-old Australian skateboarding prodigies have won their first gold medals at the X Games in California.

Chloe Covell won the women's street competition a few hours before Arisa Trew claimed the women's vert title at the coastal Ventura County Fairgrounds.

Trew had to land the first 720 by a woman in X Games competition to hold off 10-year-old Canadian Reese Nelson, who claimed silver to become the youngest medallist in the event's 29 years of history.

Covell became the youngest winner in the X Games' street skating discipline by beating a strong field including Olympic gold medallist Momiji Nishiya of Japan and Brazilian star Leticia Bufoni.

Covell had already won a bronze medal in Chiba, Japan, and a silver medal in California last year in the X Games, becoming the youngest skater with two podium finishes in the competition's history.

After another year of growth and improvement, she won gold in Ventura with an impressive final run that included a heel flip down a flight of stairs and a 50-50 kickflip.

Both Covell and Trew are from the Gold Coast.

Covell started skating at six years old after seeing American star Nyjah Huston while she watched the X Games on television with her father, Luke, a former professional rugby player.

She has shot to the top of the sport in the past two years, putting her in prime position to earn a spot in the Paris Olympics next year.

Nelson, who is from Calgary, captured the attention of Tony Hawk when she skated in an event with the world's most famous vert skater earlier this summer in Salt Lake City.