I found this on the Department of Finance Canada's website. There are 11 domestic banks and 42 foreign bank subsidiaries operating in Canada.
Most of these banks aren't really visible to the public.

UPDATE: average_joe showed me this website :) Canadian Bankers Association
http://cba.ca/index.php?option=com_content&view=category&id=61%3Abanks-operating-in-canada&Itemid=54&lang=en

According to Canadian Bankers Association there are many more domestic banks in Canada.
Banks Operating In Canada
The banking industry includes 22 domestic banks, 26 foreign bank subsidiaries and 22 full-service foreign bank branches and seven foreign bank lending branches operating in Canada. In total, these institutions manage close to $2.9 trillion in assets (Source: Office of the Superintendent of Financial Institutions as of September 30, 2009).

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Canada's Banks

September 1999
Overview

* Banks play a vital role in Canada's financial system and economic development. There are 11 domestic banks and 42 foreign bank subsidiaries operating in Canada. Most major international banks have a presence here, either through a subsidiary or a representative office.
* Banks account for over 50 per cent of the total domestic assets held by the financial services sector, which also includes insurance companies, trust companies, caisses populaires, credit unions and other financial institutions. Canada's six major domestic banks, with their wide-ranging branch networks, account for about 90 per cent of the bank industry's assets.
* The six major Canadian banks, which are significant international players, are active in the United States and throughout the world. Currently, international operations account for about 40 per cent of their net revenue.
* The Canadian banking system is regarded as highly efficient. Service fees, credit card costs and interest spreads on intermediated credit compare favourably with those of major banks in other countries.
* Canada's banks play an integral role in the national clearing and settlement system, which clears over 3 billion items valued at more than $16 trillion annually. The Canadian payments system is efficient and highly automated, with an increasing proportion of payments being made electronically.
* The six major Canadian banks have over 14,000 automated banking machines (ABMs) in Canada. In 1998, Canadians conducted over 1 billion ABM transactions and almost 1.5 billion debit card transactions.
* Capitalization levels of the Canadian banks exceed the Bank for International Settlements minimum standards.
* Although the Canadian banks have posted very strong financial results in recent years, profits and return on equity were down in 1998, largely due to weaker capital markets. Profits of the six largest banks totalled $7.1 billion in 1998, representing a 15-per-cent return on equity.
* This information sheet describes the regulatory environment that is currently applicable to the Canadian banking sector. It also discusses a major reform of the financial services sector's regulatory framework announced by the Minister of Finance on June 25, l999. The federal government will be introducing legislation to implement this policy framework as soon as feasible. The Minister's statement and the policy paper are available on the Department of Finance Web site http://www.fin.gc.ca/). Highlights of the policy paper can be found in Annex 1.
http://www.fin.gc.ca/toc/1999/Bank-eng.asp