Jennifer Lawrence's action movie pulls in £2.9 million to edge past Sam Worthington's fantasy sequel and secure the number one spot.
The race for second place was hotly contested, with Wrath taking in £2.19 million against the £2.17 haul for Aardman's latest animation The Pirates! In an Adventure with Scientists.
21 Jump Street falls two places to number four, while StreetDance 2 is at five.
The dance movie's £608,024 haul falls short of its predecessor's impressive £2,493,948 opening in 2010, which outpaced summer blockbuster Prince of Persia.
Elsewhere, Werner Herzog's film about death row inmate Michael Perry, Into the Abyss, is the only other new release to chart in the top ten.
The critically-acclaimed documentary earns £71,549 from its cinema run.
The UK box office top ten in full:
1. (1) The Hunger Games - £2,986,317
2. (-) Wrath of the Titans - £2,192,740
3. (-) The Pirates! In an Adventure with Scientists - £2,176,195
4. (2) 21 Jump Street - £962,537
5. (-) StreetDance 2 - £608,024
6. (3) The Best Exotic Marigold Hotel - £489,707
7. (4) The Devil Inside - £239,741
8. (5) We Bought a Zoo - £164,308
9. (6) Contraband - £137,497
10. (-) Into the Abyss: A Tale of Death, A Tale of Life - £71,549
Watch Digital Spy's Hunger Games interview with Jennifer Lawrence below: