Yoshi's Island DS has sold over 303,000 units in its first week of sales in Japan, placing it at the top of the charts according to data from Media Create.
The only other new entry in the Japanese top ten is Spike's Kenka Banchou 2: Full Throttle at number four, selling over 42,000 units.
There are two PlayStation 3 titles in the top 50 - Bandai's Gundam Musou at number seven and Sega's Virtua Tennis 3 at number 19. There are no Xbox 360 games in the top 50.
Hardware sales in the region have also dropped this week, with the DS selling 108,631 units and Sony's PSP shifting 56,175 units.
Nintendo has sold 44,495 Wii consoles in the past week, while Sony's PlayStation 3 has sold 32,115 units. The PlayStation 2 has sold 14,585 units, ahead of Microsoft's Xbox 360, which managed 3333 consoles sold.
The Japanese top ten follows, with weekly sales figures:
1. Yoshi's Island DS / 303,114 DS
2. Monster Hunter Portable 2 / 93,099 PSP
3. Layton Kyoujo no Fushigi na Machi / 45,344 DS
4. Kenka Banchou 2: Full Throttle / 42,131 PS2
5. Super Robot Taisen W / 36,310 DS
6. Wii Sports / 35,298 Wii
7. Gundam Musou / 31,145 PS3
8. Dragon Quest Monsters — Joker / 26,452 DS
9. Wii Play / 26,340 Wii
10. Motto Nou o Kitaeru Otona DS Training / 20,716 DS