An　experiment　was　carried　out　to　study　the　effect　of　liquid　filling　ratio,　inclination　angle,　and　type　of　working　fluid　on　the　performance　of　a　novel　flat-plate　micro　heat　pipe　(FPMHP).　The　FPMHP　is　developed　based　on　a　multiport　micro/minichannel　flat　tube,　capable　of　the　advantages　such　as　the　simple　manufacturing　process,　flexible　structure,　good　isothermal　performance　and　heat　transport　with　a　long　distance.　Results　shows　that　a　filling　ratio　has　a　significant　effect　on　thermal　performance,　and　a　FPMHP　with　a　filling　ratio　of　20%　has　the　best　performance.　The　temperature　distribution　along　the　adiabatic　section　showed　nearly　no　difference　between　two　measuring　points,　indicating　that　the　FPMHP　is　able　to　employed　as　a　high-efficiency　heat　transfer　equipment　of　phase　change.　FPMHP　performance　was　improved　remarkably　when　the　inclination　angle　increased　from　0　degrees　to　20　degrees　due　to　the　effect　of　gravitational　and　buoyancy　force,　but　the　performance　difference　was　negligible　when　the　inclination　angle　increased　from　20　degrees　to　90　degrees.　For　different　working　fluids,　the　higher　transmission　factor,　the　better　working　fluids　thermal　performance.　Thus,　the　FPMHP　using　methanol　has　the　best　performance,　with　a　minimum　thermal　resistance　of　0.18　K/W　and　a　maximum　thermal　conductivity　of　8539　W/mK,　respectively.