'Dynamite' becomes the singer's first number one, following previous number two hit 'Break Your Heart'. Cruz knocked Eminem and Rihanna down a spot to second place.
Brandon Flowers's 'Crossfire' jumps 31 places to number four, just ahead of Travis McCoy featuring Bruno Mars.
Elsewhere in the chart, Ke$ha's 'Take It Off' climbed ten into the top 20 while Rumer's 'Slow' is a new entry at 33.
The Irish top ten singles in full:
1. (26) Taio Cruz: 'Dynamite'
2. (1) Eminem ft. Rihanna: 'Love The Way You Lie'
3. (2) Flo Rida ft. David Guetta: 'Club Can't Handle Me'
4. (35) Brandon Flowers: 'Crossfire'
5. (3) Yolanda Be Cool & DCUP: 'We No Speak Americano'
6. (5) Travie McCoy ft. Bruno Mars: 'Billionaire'
7. (4) B.o.B ft. Hayley Williams: 'Airplanes'
8. (6) Eliza Doolittle: 'Pack Up'
9. (7) Swedish House Mafia: 'One (Your Name)'
10. (11) Katy Perry: 'California Gurls'
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