f(x)'s Sulli is looking absolutely stunning and summer ready in her new photoshoot for 'Cosmopolitan'!

Posing with the beautiful background of Bali behind her, Sulli shows off her flat midriff in a cropped top and bikini bottom. She also shows how to cover up in style when she's outside of the water in the other photos, looking like an heiress taking a vacation at the beach!

Sulli shows she's not a young girl anymore, and she's growing into a beautiful woman.

Take a look at the photos below, or you can see her in the June issue of 'Cosmopolitan'.