The　optimization　of　the　extraction　process　of　protein　from　Gracilaria　lemaneiformis　was　achieved　by　response　surface　methodology　and　its　antioxidant　activity　were　characterized.　Gracilaria　lemaneiformis　protein　extraction　rate　was　taken　as　the　index　to　study　the　effect　of　ratio　of　liquid　:　material(V/m),　NaOH　concentration,　extraction　temperature　and　extraction　time　on　extraction　yield.　On　the　basis　of　single　factor　experiment,　the　four　factors　and　three　levels　of　response　surface　analysis　method　was　taken　to　determine　the　Gracilaria　lemaneiformis　protein　extraction　process.　The　results　showed　that　ratio　of　liquid　:　material(V/m)　of　17　:　1,　NaOH　concentration　of　0.2　mol/L,　extraction　temperature　of　62　and　extraction　time　of　2.5　h　were　optimal　for　protein　extraction　from　Gracilaria　lemaneiformi　and　the　extraction　ratio　was　84.88%.　The　concentration　for　50%　of　maximal　effect(EC50)　of　Gracilaria　lemaneiformi　protein　extracted　under　the　optimal　condition　to　DPPH　radicals,　Hydroxyl　radical　and　ABTS　radicals　were　0.50　mg/mL,　1.0　mg/mL　and　0.05　mg/mL,　which　showed　that　protein　extraction　from　Gracilaria　lemaneiformi　has　certain　antioxidant　activity.　©　2018,　Editorial　Office　of　Journal　of　CIFST.　All　right　reserved.