How to create local repository using redhat ISO image

1. Create mount point for ISO file.
Assume the Redhat ISO image is located at /root/rhel-server-6.4-x86_64-dvd.iso.

mkdir -p /root/rhel_image
mount /root/rhel-server-6.4-x86_64-dvd.iso /root/rhel_image -o loop

2. Create local repository in /etc/yum.repos.d/

# cat rhelLocal.repo
[rhel6.4]
name=Redhat_local
baseurl=file:///root/rhel_image
enabled=1
gpgcheck=0
protect=1

3. List current repository

yum repolist

More details please refer to Creating a Redhat package repository.
If you need EPEL(Extra Packages for Enterprise Linux), refer to How to Enable EPEL Repository for RHEL/CentOS 7.x/6.x/5.x.