In　order　to　improve　the　anticancer　activity　of　emodin,　seven　emodin　derivatives　containing　nitrogen　heterocycle　and　three　emodin　derivatives　containing　quaternary　ammonium　salt　were　designed　and　synthesized　by　suitable　modification　at　C6　position　of　emodin,　their　structures　were　characterized　by　IR,　H-1　NMR　and　MS　and　their　activities　against　leukemia　cell　line　Molt-4　and　lymphoma　cell　line　CA46　in　vitro　were　tested　by　MTT　method.　Thereinto,　compounds　8,　9a+9b,　20a,　20b　and　20c　show　higher　anticancer　activities　than　emodin,　which　indicates　that　benzimidazole　and　quaternary　ammonium　salt　are　good　pharmacophores　for　the　anticancer　activity　of　emodin.　We　propose　to　introduce　many　such　pharmacophores　into　emodin　to　improve　the　anticancer　activity　of　emodin　in　further.