We　report　an　efficient　and　easily　accessible　self-assembly　route　to　synthesize　In2S3-GR　nanocomposites　via　electrostatic　interaction　of　positively　charged　In2S3　nanoparticles　with　negatively　charged　graphene　oxide　(GO)　followed　by　a　hydrothermal　process　for　reduction　of　GO　to　graphene　(GR).　The　as-synthesized　In2S　3-GR　nanocomposites　exhibit　much　higher　visible　light　photocatalytic　activity　toward　selective　reduction　of　nitroaromatic　compounds　in　water　than　bare　In2S3　nanoparticles　and　In2S　3-GR-H　that　is　obtained　from　the　simple　＂hard＂　integration　of　GR　nanosheets　with　solid　In2S3　nanoparticles　without　modification　of　surface　charge.　On　the　basis　of　the　joint　characterizations　and　structure-photoactivity　correlation　it　is　disclosed　that　the　enhanced　photocatalytic　performance　of　In2S3-GR　is　mainly　ascribed　to　the　more　efficient　interfacial　contact　between　In2S3　and　the　GR　nanosheets　than　In2S3-GR-H,　which　would　amplify　the　use　of　electron　conductivity　and　mobility　of　GR　to　improve　the　lifetime　and　transfer　of　photogenerated　charge　carriers　more　efficiently　and　thus　boost　the　photoactivity　more　effectively.　This　work　highlights　the　significant　effect　of　preparation　methods　on　the　photoactivity　of　GR-semiconductor　nanocomposites.　It　is　expected　that　such　a　simple　electrostatic　self-assembly　strategy　could　aid　to　rationally　fabricate　more　efficient　GR-semiconductor　nanocomposites　with　improved　interfacial　contact　and　photocatalytic　performance　toward　various　photocatalytic　selective　transformations.　©　2013　American　Chemical　Society.