This is one of the restaurants that I always visit whenever I visit Thailand. Though it's not the very best Japanese food you can have, the food served are quite good and cheap too. They have many branches all around Thailand and it's quite difficult to not find one in Bangkok. If you're on a tight budget, Fuji Japanese restaurant in Thailand is one that would be friendly to your wallet.
Fuji Steak
Pork roll with mushroom and cheese in the middle
Cha Soba (Cold noodles)
Grilled Squid
Of all the dishes, the first dish is my favorite and it's the one dish that will be ordered every time I go. The meat is always cooked to perfection with the middle still being slightly pink. All in all my meal there for 2 person cost around 650 baht (approx. S$26).