The pop beauty, who reached the landmark age on June 30, partied at Hakkasan nightclub in Las Vegas till 3.45am on Sunday morning (30.06.13).
The group who were joined by other friends were seen drinking vodka and Red Bull combos as they danced.
Cheryl was seen enjoying a cigarette inside the venue where lighting up is still legal in establishments not serving food.
The star was inundated with birthday wishes from her millions of fans on Twitter and she tweeted: ''''Awwww!!! Thank you all sooo much for my birthday wishes. You are the sweetest!!!!!! (sic)''
Cheryl - who was previously married to soccer player Ashley Cole - spent £50,000 to mark the occasion, treating her best friends and family to an all-expenses paid, two-day trip to the US city.
A source previously said: ''Cheryl's been through so much in the past few years, and she's actually really proud to reach the age of 30. She's not one of these girls to mope about her age, instead she sees it as a great chance to celebrate.''