1.进入virtualbox官网

https://www.virtualbox.org/

2.点击download

3.点击Linux distributions

4.向下翻至如图，并且进入同种框选页面

5.在/etc/yum.repos.d/目录下新建virtualbox.repo并写入如下内容

[virtualbox]
name=Oracle Linux / RHEL / CentOS-$releasever / $basearch - VirtualBox
baseurl=http://download.virtualbox.org/virtualbox/rpm/el/$releasever/$basearch
enabled=1
gpgcheck=1
repo_gpgcheck=1
gpgkey=https://www.virtualbox.org/download/oracle_vbox.asc

6.更新yum缓存

yum clean all

yum makecache

7.安装virtualbox

yum install VirtualBox-5.1

CentOS7安装virtualbox