The HPV vaccine will be extended to all teenage boys in Wales following a review.
It has been available to girls aged between 12 and 13 since 2008 but teenage boys who wanted the vaccination had to pay for it privately.
However, a review by Joint Committee on Vaccination and Immunisation (JCVI) found that making the vaccine available to teenage boys would reduce the number of HPV related cancer cases and deaths.
Vaughan Gething, Cabinet Secretary for Health and Social Services says he is pleased about the decision.
The human papillomavirus (HPV) is a common infection which is spread through skin contact, often through sex.
It is known to cause cancer of the cervix, throat (oropharyngeal), anus and penis.
Doctors say the virus is usually contracted in the teenage years but those infected with HPV often do not experience any symptoms and may not know they have it until they are diagnosed with cancer in later life.
Political parties including Plaid Cymru and the Welsh Liberal Democrats have previously campaigned for the vaccine to be extended.
In interim advice in 2017 the JCVI had warned that vaccinating boys may not be cost effective.
The Royal College of GPs (RCGP) has welcomed the change in direction.