The duo, whose track has spent a total of 16 weeks on the chart, holds on to the top spot for a second week, fending off Pitbull's 'Give Me Everything' and Adele's 'Rolling in the Deep' at two and three respectively.
Elsewhere in the Top 10, Katy Perry's 'Last Friday Night' spends a fourth week at number four and Lil Wayne's 'How to Love' advances from eight to seven, while One Republic's 'Good Life' climbs from nine to eight.
Further down the chart, Frank Ocean's 'Novacane' debuts at 82, J Cole's 'Work It Out' starts at 85 and Avril Lavigne's 'Smile' debuts at 94.
The Top 10 singles in full (click where possible for our reviews):
1. (1) LMFAO ft. Lauren Bennett & GoonRock: 'Party Rock Anthem'
2. (2) Pitbull ft. Ne-Yo, Afrojack and Nayer: 'Give Me Everything'
3. (3) Adele: 'Rolling in the Deep'
4. (4) Katy Perry: 'Last Friday Night'
5. (5) Nicki Minaj: 'Super Bass'
6. (6) Lady GaGa: 'The Edge of Glory'
7. (8) Lil Wayne: 'How to Love'
8. (9) One Republic: 'Good Life'
9. (10) Hot Chelle Rae: 'Tonight Tonight'
10. (7) Katy Perry ft. Kanye West: 'E.T.'
Watch LMFAO's 'Party Rock Anthem' music video below: