Preheat grill for medium heat and lightly oil the grate.
Whisk orange juice, brown sugar, rice vinegar, soy sauce, chile paste, fish sauce, and garlic in a large bowl. Add skirt steak and marinate for 15 minutes.
Cook steaks on the preheated grill until they are browned and are hot and slightly pink in the center, about 4 minutes per side. An instant-read thermometer inserted into the center should read 140 degrees F (60 degrees C).
