Is an 11-year-old girl overweight if she weighs 121 and is 4'9?

You should weigh 80-95 pounds, and you are well outside that range. So technically yes, but if you have a large build, or if you're in puberty, then you're okay.

if youre only 4'9 and you way 121 i would say youre overweight bt its not really that bad i mean you can loose it easily since youre young!!!!