Shanti Epicerie

A rather large store; far from the city center and not easily accessible, but they have a lot of stuff I never found elsewhere, including a large range of vegan chocolates or "crème épaisse" (Sojami).
They also have choice of non food (cosmetics, books, etc)
Sadly the store is not vegeatrian (nor is the restaurant upstairs)

My favorite spot for the vegetarian foodstuffs and more. They have probably the largest selection in Brussels. According to me, it's a little bit less expensive than others stores in town.
They are everything from organic soy sauce to organic gluten-free beers

You can find almost everything here. I find it the easiest place to shop for organic vegan food in Brussels. They have quite a lot of staff, so there's always someone to help you out if you're looking for something specific and they even offer to order food they don't usually sell if they don't have what you're looking for. They do offer animal products, but it's quite easy to find the vegan stuff. They even sell raw vegan snacks and also have a wide range of gluten free food.

Biggest organic store in town. Here ou can find a great choice in fresh food (lots of vegan stuff), bulk cereal and grains, vegetables milk, and a few fresh fruits and vegetables.
There is a wide range in organic cosmetic products too.
A bit pricey, as every organic shop in Belgium/France.
A lot of very cool vegan german products you can't find in France, for example.