Utilization　of　protein-based　nanoparticles　encapsulating　resveratrol　is　hampered　by　their　instability　against　the　environmental　stress　including　pH,　ionic　strength　and　UV　light.　In　this　study,　we　fabricated　a　sodium　alginate　(Alg)-shelled　soy　protein　isolate　(SPI)　nanoparticle　for　the　encapsulation　of　resveratrol,　abbreviated　as　RSAN.　The　aim　of　this　study　was　to　investigate　the　existence　of　Alg　shell　on　both　colloidal　and　chemical　stabilities　of　RSAN.　RSAN,　fabricated　at　pH　3.5　and　0.25　mg/mL　of　Alg,　is　204.5　+/-　12.1　nm　in　diameter,　-36.4　+/-　1.2　mV　in　zeta-potential　and　91.9　+/-　3.3%　in　encapsulation　efficiency　of　resveratrol.　RSAN　exhibited　consistent　solubility　from　pH　2.0　to　8.0　and　was　resistant　to　precipitation　in　ionic　strength　of　400　mM　NaCl　at　various　pHs.　The　protein　in　RSAN　was　prevented　from　digestion　in　gastric.　Only　15%　trans-resveratrol　in　RSAN　was　isomerized　after　30　min　UV　light　exposure,　which　is　approximate　30%　less　than　the　non-shelled　nanoparticle　(RSN).　Moreover,　the　encapsulation　of　resveratrol　did　not　reduce　its　antioxidant　activity.　The　findings　suggest　that　this　Alg-shelled　nanoparticle　has　a　potential　in　encapsulating　hydrophobic　bioactive　compounds　for　utilization　in　functional　foods.