The 21-year-old defeated tough competition in the shape of Glastonbury favourites Example and Beyoncé to extend his reign at number one.
Example's 'Changed The Way You Kissed Me' remains in the runner-up spot, while album chart champion Beyoncé snags the highest new entry of the week with 'Best Thing I Never Had' at three.
Elsewhere, Katy Perry takes 'Last Friday Night (T.G.I.F.)' into the Top 10 for the first time after climbing two places to nine, while Coldplay round out the top-sellers with 'Every Teardrop Is A Waterfall'. The track slipped out of the rankings last week, but jumped an incredible 32 entries after a magnificent show at Glastonbury.
Meanwhile, Nicki Minaj continues to sneak towards the Top 10 with 'Super Bass', up another three places to 12, as Aloe Blacc falls the same amount to land behind her at 13 with 'I Need A Dollar'.
Also tripping down the chart this week is Nicole Scherzinger's 'Right There', down six to 15, while The Saturdays finally manage to break back into the top 20 with after climbing three to 18 with 'Notorious'.
Tinchy Stryder's 'Spaceship' and 'I'm Into You' by Jennifer Lopez conclude the upper half of the chart after sliding six and four respectively to 19 and 20, watching as Beyoncé just fails to score a second entry in this week's top 20 with 'Run The World (Girls)', up 16 to 23.
The Top 10 in full:
1. (1) Jason Derülo: 'Don't Wanna Go Home'
2. (2) Example: 'Changed The Way You Kissed Me'
3. (-) Beyoncé: 'Best Thing I Never Had'
4. (3) Calvin Harris ft. Kelis: 'Bounce'
5. (4) Pitbull ft. Ne-Yo, Afrojack and Nayer: 'Give Me Everything'
6. (5) Ed Sheeran: 'The A Team'
7. (8) Lady GaGa: 'The Edge Of Glory'
8. (6) Alexandra Stan: 'Mr Saxobeat'
9. (11) Katy Perry: 'Last Friday Night (T.G.I.F.)
10. (42) Coldplay: 'Every Teardrop Is A Waterfall'
Source: Official Charts Company
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