1) rpm -qa | grep firefox查询已安装的旧版firefox2) rpm -e firefox-45.4.0-1.el7.centos.x86_64 删除旧版firefox如果提示错误：error: can't create transaction lock on /var/lib/rpm/.rpm.lock (Permission denied)，是因为权限不够，加上sudo命令并输入密码sudo rpm -e firefox-45.4.0-1.el7.centos.x86_64