Croatia's two-time world champion Sandra Perković will compete in the women's discus throw Also, Marija Tolj, the new champion from the Mediterranean Games, will be the other Croatian representative in this event.
Sara Kolak, who grabbed the gold at the Rio De Janeiro Olympic Games, will represent Croatia in the women's javelin throw event.
National record holder in the shot put, Filip Mihaljević, and Martin Marković, who won the silver in shot put at the recent Mediterranean Games, will be the two Croatian male competitors at the championships in the USA.
Over 1,900 athletes have applied for the championships.
The oldest contestant will be Kelly Ruddick, 49, an Australian race walker.
The youngest contestant is also in the Australian team, 17-year-old Claudia Hollingsworth in the women's 800m.