Lasting　large-scale　events　are　defined　as　large　activities　or　events　held　for　many　days.　It　is　important　to　reveal　influencing　factors　and　the　influencing　mechanism　to　the　passenger　flow　for　the　organization　of　transportation　operation　for　these　events.　This　study,　based　on　the　passenger　flow　of　the　9th　China　International　Garden　Expo,　collects　passage　volumes　through　the　ticket　gate,　observes　the　passenger　flow　through　an　automated　method,　and　analyzes　the　characteristics　of　trip　mode,　passenger　arrival,　and　departure,　as　well　as　the　influence　factors　of　passenger　flow　scale,　over　a　four-month　span.　Analysis　shows　that　weather　and　holidays　are　the　main　influencing　factors　on　passenger　flow　scale.　This　analysis　will　contribute　to　the　study　of　traffic　impact　model　of　special　events,　and　provide　effective　data　support　to　make　valid　traffic　organization　and　management　measures　during　lasting　large-scale　events.　©　2018　American　Society　of　Civil　Engineers.