Charmaine Holmes, 17, pled guilty yesterday at Glasgow Sheriff Court to the assault on PC Clare Connelly on December 6, 2013 at Ballater Street.
She was accused of biting the officer on the arm but pled guilty when the charge was changed to headbutting her arm.
She also admitted breaching bail.
Sentence was deferred until later this month and her bail was continued.
Holmes pled guilty to breaking into the Clutha with three others and stealing alcohol and cash weeks after 10 people tragically lost their lives.
The teenager was given a community payback order for 18 months with the condition she will be supervised.
Billy Jo Revie, 16, was given the same sentence and Jordan Parry, 16 and Darren Melrose, 18, were given six months detention after pleading guilty to the offence.
An air accident investigation found the police helicopter suffered a double engine failure when it came down on November 29 last year.
The Air Accident Investigation Branch (AAIB) said both engines of the Eurocopter EC 135 "flamed out" but its report did not pinpoint the cause. Some commentators have suggested a problem with the fuel supply.
All three people on board and seven others in the pub were killed.
In its report, published in February, the AAIB said that its investigation into the crash was still ongoing.
Investigators are still trying to establish why both engines "flamed out" when there was 76kg of fuel remaining.
Examination of the engines showed "no evidence of foreign object damage or exhaust blockage in either".
A memorial service was held in March at St Andrew's Cathedral.