Freeway　debris　poses　a　threat　to　driving　safety,　emphasizing　the　crucial　importance　of　assessing　the　risk　level　associated　with　freeway　debris　incidents.　This　study　devised　a　simulated　driving　experiment　plan　for　assessing　freeway　debris　incidents　under　the　influence　of　three　factors:　debris　type,　lane　position,　and　lighting　condition.　The　basic　operational　data　of　drivers　were　collected　in　various　driving　scenarios.　An　assessment　indicator　system　was　established　using　six　indicators:　speed　standard　deviation,　lane-changing　point　location,　maximum　steering　wheel　angle,　maximum　steering　wheel　speed,　lane　gap　standard　deviation,　and　acceleration.　The　risk　level　of　different　freeway　debris　incidents　was　assessed　using　the　factor　analysis　method.　The　results　indicate　that　the　risk　level　of　debris　incidents　is　ranked　as　follows:　tire　＞　wooden　crate　＞　tarpaulin　＞　plastic　bottle,　lane　1　＞　lane　2,　nighttime　＞　daytime.　This　study　can　provide　a　theoretical　basis　for　early　warning　and　control　of　freeway　debris.　©　ASCE.