The preferred way to install PHPMD should be the PEAR installer and PHPMD's PEAR channel, where you will always find the latest stable version. Because PHPMD heavily relies on metrics measured with PHP Depend you must also discover this project's PEAR Channel. Just enter:

~ $ pear channel-discover pear.phpmd.org

~ $ pear channel-discover pear.pdepend.org

~ $ pear install --alldeps phpmd/PHP_PMD

from ： http://phpmd.org/download.html