I've got to admit, I'm not well-read enough to even come up with a candidate.
Nominees?

Michael Ondaatje's "In The Skin of a Lion"?

Or Cheryl Bernard's curling book.

Here are a few of my favourites.

Life of Pi--Yann Martel
The Stone Angel--Margaret Laurence
The Stone Diaries--Carol Shields
Alias Grace--Margaret Atwood (Actually, I'd recommend anything she's written since The Handmaid's Tale)
Fifth Business--Robertson Davies
In the Skin of a Lion--Michael Ondaatje
Who has seen the Wind?--W.O. Mitchell

The Boat Who Wouldn't Float- Mowat
Cabbagetown- Garner
Fifth Business- Davies

Davies "Fifth Business" is one of my favorites.

That's where I first met Magnus Eisengrim.

Fifth Business was the one I thought of.
I have to admit I didn't know that Margaret Atwood and Yann Martel were Canadian.

Canadian literature really didn't come of age until about 1960. Probably the most significant Canadian form is not the novel,but the cycle of short stories. It is worth checking out Margaret Laurence's A Bird in the House, Alice Munro's Who do you Think you Are? or Lives of Girls and Women, and Mavis Gallant's Home Truths.

The ground-breaking novel in French was probably Gabrielle Roy's Bonheur d'occasion, (The Tin Flute, in English); many credit it as being an important influence on Quebec's "Quiet Revolution".

By now, you've probably noticed that Canadian literature is dominated by female writers. It's well-known, and AFAIK nobody has any idea why this might be so.

For my money, there has been a very exciting turn in Canadian writing in the past couple of decades with the rise of First Nations writers. I recommend you check out Thomas King's Green Grass, Running Water as a terrific example of this new voice (King, BTW is a dual USA-Canadian citizen). And the most interesting voice in contemporary Canadian drama is probably Tomson Highway, a Cree playwright. Check out his The Rez Sisters, or Dry Lips Oughta Move to Kapuskasing.

I just read this one last week and loved it.
http://www.chapters.indigo.ca/books/the-......tem.html

If you've ever read Frank McCourt's book, Angela's Ashes, you'll love this one as it's based on this Canadian author, Ian Ferguson, childhood who grew up in a predominately impovrished aboriginal community. His father was running from the law and takes his family into a community that was closed off from the rest of the world when the river froze over each winter. The author, was saved from death by the aboriginal medicine man when traditional meds couldn't save him and is from that moment on considered aboriginal. His life experiences, insights, childhood, the various characters of the village and later his reflections of where he came from will have you not wanting to put this book down.

There is also the classic Canadian novels - Fifth Business and Stone Angel which most Canadian kids have read as it's on the list in most school districts for required novel studies.