In　the　digital　era,　effectively　managing　rumors　on　social　media　during　public　health　emergencies　remains　a　significant　challenge,　highlighting　a　gap　in　understanding　the　optimal　strategies　for　refutation.　This　study　used　the　COVID-19　pandemic　as　a　case　to　explore　the　effectiveness　of　different　rumor　refutation　strategies　on　social　media　during　acute　public　health　emergencies,　with　a　specific　focus　on　the　moderating　effects　of　the　elements　contained　in　the　refutation　texts　based　on　the　5　W　theory.　By　leveraging　the　comprehensive　and　structured　nature　of　the　5　W　elements　(What,　When,　Where,　Who,　and　Why),　this　study　provides　a　novel　framework　for　evaluating　and　optimizing　refutation　strategies.　A　total　of　22,648　refutation　posts　related　to　COVID-19　from　the　Weibo　platform　in　2020　were　employed　from　empirical　analysis.　Findings　indicate　that　the　combination　of　direct　refutation　with　factual　clarification　is　more　effective　in　enhancing　the　credibility　and　dissemination　of　reputation　information　compared　to　isolated　strategies.　Importantly,　the　study　highlights　the　moderating　role　of　specific　rumor　characteristics,　such　as　the　rumor＇s　name,　location,　and　the　underlying　reasons,　on　the　effectiveness　of　these　strategies.　Furthermore,　the　study　provides　practical　policy　recommendations　based　on　empirical　findings.　Overall,　this　research　enriches　the　academic　discourse　on　rumor　management,　offering　innovative　applications　of　the　5　W　theory　and　detailed　analysis　of　moderating　effects,　and　provides　empirical　guidance　for　public　health　communicators　and　policymakers　in　tailoring　refutation　strategies　to　specific　characteristics　of　rumors　for　more　effective　rumor　containment.