A　colorimetric　hydrogen　sulfide　(H2S)　sensor　based　on　gellan　gum　capped　silver　nanoparticles　was　developed　to　real-time　monitor　meat　spoilage.　The　colorimetric　sensor　strategy　was　attributed　to　the　ultrastrong　binding　ability　of　Ag　with　H2S　to　form　Ag2S.　The　sensor　enables　the　analysis　of　H2S　with　a　limit　of　detection　(LOD)　of　0.81　mu　M,　and　it　exhibited　excellent　selectivity　toward　H2S　against　other　volatile　components　generated　from　chicken　breast　and　silver　carp　during　spoilage.　By　these　virtues,　the　sensor　presented　visible　color　changes　from　yellow　to　colorless　by　in　situ　and　nondestructively　sensing　H2S　generated　from　chicken　breast　and　silver　carp　in　a　packaging　system.　This　strategy　provided　a　simple　but　useful,　non-destructive,　robust,　cost-effective,　and　userfriendly　platform　to　real　time　monitor　meat　spoilage　for　intelligent　food　packaging.