It has been a while since I have been to Hamachi. I used to go frequently as a vegetarian. The vegetarian options are labled on their menu. I love the fact that you are offered a CHOICE of miso soup or salad with the vegetarian combos(their miso soup contains fish). Other Japanese restaurants include it in their vegetarian meals.
Vegan options aren't labeled, so you'll have to ask about them.
If you're vegetarian and like maki, I recommend the preggo roll.
I love the restaurant. The walls are painted blue with fish. I feel like I am dining under the ocean.Pros: nice atmosphere, many vegetarian options
Cons: vegan items aren't labeled