| Rank | LW | Release
| Gross | %± LW | Theaters | Change | Average | Total Gross | Weeks | Distributor
| New This Week
| Estimated
|
|---|
| 1 | 1 | Phobia 2 | $207,457 | -57.9% | 129 | -12 | $1,608 | $3,117,931 | 3 | GMM Tai Hub (GTH) | false | false |
| 2 | 2 | The Proposal | $149,864 | -38.7% | 42 | -9 | $3,568 | $566,158 | 2 | Walt Disney Pictures | false | false |
| 3 | 3 | District 9 | $120,566 | -40.1% | 50 | -4 | $2,411 | $438,719 | 2 | M Pictures | false | false |
| 4 | - | Pandorum | $105,692 | - | 78 | - | $1,355 | $105,692 | 1 | Mongkol Major | true | false |
| 5 | 4 | Dreamaholic | $90,382 | -53.2% | 65 | -4 | $1,390 | $355,916 | 2 | Mongkol Film Company | false | false |
| 6 | 5 | The Final Destination | $46,310 | -36.9% | 55 | -3 | $842 | $1,318,636 | 4 | Warner Bros. | false | false |
| 7 | 6 | Whiteout | $29,791 | -42.4% | 39 | -2 | $763 | $114,137 | 2 | Warner Bros. | false | false |
| 8 | 7 | Gamer | $9,221 | -26.4% | 27 | -6 | $341 | $374,775 | 4 | M Pictures | false | false |
| 9 | 18 | Land of the Lost | $4,475 | +276.7% | 6 | +3 | $745 | $37,063 | 4 | United International Pictures | false | false |
| 10 | 8 | My Ex | $2,479 | -67.3% | 25 | -1 | $99 | $1,415,217 | 5 | RS Film & Distribution | false | false |
| 11 | - | Rookies the Movie: Graduation | $2,106 | - | 2 | - | $1,053 | $2,106 | 1 | N/A | true | false |
| 12 | 9 | 9 | $1,988 | -49.1% | 1 | - | $1,988 | $17,394 | 3 | M Pictures | false | false |
| 13 | 15 | Coco Before Chanel | $1,722 | +20.7% | 5 | +1 | $344 | $63,691 | 6 | N/A | false | false |
| 14 | 16 | Ponyo | $1,540 | +9.5% | 2 | - | $770 | $25,194 | 5 | M Pictures | false | false |
| 15 | 17 | Inglourious Basterds | $1,461 | +6.5% | 3 | +1 | $487 | $304,035 | 6 | United International Pictures | false | false |
| 16 | 12 | Transformers: Revenge of the Fallen | $1,182 | -34.2% | 9 | -3 | $131 | $5,929,888 | 14 | United International Pictures | false | false |
| 17 | 13 | Crows Zero II | $1,002 | -39.1% | 1 | - | $1,002 | $7,017 | 3 | N/A | false | false |
| 18 | 10 | My Sister's Keeper | $883 | -70.1% | 3 | -2 | $294 | $19,126 | 3 | Warner Bros. | false | false |
| 19 | 14 | Harry Potter and the Half-Blood Prince | $700 | -53.8% | 1 | - | $700 | $4,076,379 | 11 | Warner Bros. | false | false |
| 20 | 19 | G.I. Joe: The Rise of Cobra | $307 | -44.8% | 2 | - | $153 | $2,380,237 | 8 | United International Pictures | false | false |
| 21 | 11 | The Naked Kitchen | $155 | -92.9% | 2 | -8 | $77 | $13,561 | 3 | Mongkol Major | false | false |
