Now i can use command:
mysql -h localhost -u root -p
connect to mysql server.

But when i use command:
mysql -h 127.0.0.1 -u root -p
or:
mysql -h 10.0.0.1 -u root -p (10.0.0.1 is the IP of mysql server)
i failed,why? and how can do ?

Thanks.

I typically use the command

mysql -h10.0.0.1 -u root -ppassword (where password is some password)

or

mysql -h10.0.0.1 -u root

if there is no password on the remote mysql server.

Also make sure mysql is currently running on the remote server.