Hello dear
I want to transfer money to my saving account to canada ,shall I pay tax for it &how much?

Are you a Canadian citizen or permanent resident? There is no tax on importing money but if your only a visitor then Canada Customs will question you if the amount is very high.

You must declare the transfer of funds at the border (even online tranfer) if it is more than CAD $10,000

RC4321 - Crossing the Border With $10,000 or More? (http://www.cbsa-asfc.gc.ca/E/pub/cp/rc4321/README.html)

Not my area of expertise, but what LowTax says matches what would happen if you had the money imported to the U.S.