Montreal has many public markets, like Atwater, Maisonneuve or Jean-talon ..
I like especially Jean-talon market, it is full of ambiance, the atmosphere is very good, farmers come here to sell their fresh fruits, vegetables and other home made stuff, every thing is organized in symphony of colors and there are always samples for taste ;))
Also what make it nicer, arround the market there are some small restaurants and cafes with terrace.
My favorite thing there is: eat a merguez or lamb sandwith, some fruit dessert from the market and cafe in the terrace cafe ;)
Atwater Market!! Itýs a good walk from the Lionel Groulx metro, but you can choose a local wine, old fashioned bread, tempting bakery treats, fresh croissants, marvel at the meats, buy organic foods and fresh fruits from the many upscale vendors here.
Hands down, Pizza Ancora at the Atwater Market is the best pizza in the city. Choose your favorite from an interesting and luscious array of artfully crafted pizzas. Eat there and refuel after shopping in the delicious stores at Atwater market or take some home and reheat for the fanciest pizza dinner ever.
Go to Atwater Market. This is a little open air market with a few shops inside. The vegatable stands are pretty enough, you will want to take a picture. Great selections of meats and cheeses. Inside upstairs is a shop that sells things out of big bins. It is like a french gormet's Mr. Bulky's.
The Atwater Market is accessable from the Lionel-Groulx Metro Station. Go south from the metro stop, near the corner of Rue Atwater and Rue Notre Dame.