©　2016　by　Nova　Science　Publishers,　Inc.　Oxygen　is　critical　for　living　creatues　to　generate　energy;　however,　it　can　be　detrimental　to　cause　cancer,　aging　etc.,　when　the　resultant　reactive　oxygen　species　(ROSs)　and　antioxidant　defence　are　not　in　the　balance.　As　a　typical　example,　phenol-containing　molecule　plays　a　important　role　in　acting　against　ROS.　This　chapter　describes　the　very　recent　development　of　new　synthetic　phenol-containing　polymers　as　effective　free　radical　scavengers　in　aqueous　environment,　such　as　a　phenolic　resin　(particularly　novolac　resin)　grafted　with　hydrophilic　poly(ethylene　glycol)　(PEG)　by　click　chemistry.　Due　to　the　amphiphilic　nature,　the　new　polymer　selfassembles　to　form　colloidally-stable　micelles　with　hydrophobic　novolac　cores　surrounded　with　hydrophilic　PEG　chains.　The　micelles　exhibit　noncytotoxicity　and　quick　response　to　hydroxyl　radicals,　protecting　indicator　molecule　Crystal　Violet　from　being　bleached　in　water.　Further,　another　phenol-containing　polymeric　radical　scavenger,　a　catecholcontaining　polymer　synthesized　from　dopamine　by　free　radical　polymerization,　is　presented.　The　new　research　including　nano-aggregates　by　self-assembly　enriches　the　synthetic　methodologies　in　fighting　against　ROS　in　the　future.