Matthews, 23, is currently contracted with the Gold Coast Titans and has agreed to join the Dragons on a two-year contract that will see him remain at the club until at least the end of 2013.
The versatile former Kyogle junior can play in both the front and back row and made his NRL debut against the Dragons in Round 16 of the 2008 season.
Additionally, Latimore, 24, has agreed to a one-year contract that will see the prop join the Club for one season, at least until the end of 2012.
The Port Macquarie junior started his career with the Parramatta Eels in 2009 before joining the Warriors last season and has made a career total of 31 NRL appearances to date.
Matthews and Latimore will join the Dragons in November.