I use RHEL 5, set up named server as in documentation, setup named.conf in /var/named/chroot/etc.
I ran "named-checkconf named.conf", return no error.
When I want to start the named service, it has the following error:
stating named:
Error in named configuration:
/etc/named.conf:58: open: /var/named/chroot/etc/named.root.hints: file not found

The file is there, but not found.
Please help.

As the "chroot" in path implies you're using a special build of BIND that uses a jailed directory. The point in such a jail is to prevent anyone that hacks into your system from being able to go above the jail's apparent root (the chroot).

From within the system you see the chroot as /var/named/chroot. From outside the system if someone hacked in they would see it as just "/". Also the running named sees this as "/".

This means all references used within /var/named/chroot should ignore the fact they are there and be made relative to "/" rather than /var/named/chroot.

Accordingly your: /var/named/chroot/etc/named.root.hints on line 58 is wrong. It should simply read "/etc/named.root.hints" instead.