The　performance　of　asphalt　pavement　shows　different　forms　of　decay　with　increased　service　life　of　expressways　in　China,　which　affect　driving　safety　and　comfort.　Actively　taking　preventive　maintenance　treatments　can　further　improve　the　pavement　performance.　However,　there　are　relatively　few　studies　on　the　improvement　effectiveness　of　various　preventive　maintenance　treatments　in　China.　The　data　foundation　of　this　paper　is　the　pavement　performance,　maintenance　history,　and　other　multivariate　data　of　expressways　in　Beijing.　This　paper　analyzes　the　performance　distribution　characteristics　of　Beijing　expressway　pavement　from　a　macro　perspective　and　uses　mathematical　evaluation　method　to　evaluate　the　effectiveness　of　three　preventive　maintenance　treatments　(thin　overlay,　micro　surface,　and　fog　seal)　on　the　PCI　performance　index.　The　results　show　that　the　improvement　effectiveness　of　treatment　is　the　best,　followed　by　micro　surface.　However,　the　fog　seal　treatment　is　poor;　it　can　only　delay　the　decay　rate　of　PCI.　We　recommend　using　the　thin　overlay　treatment　when　PCI　is　at　a　good　level　or　below　(PCI　＜　92).　When　PCI　is　at　an　excellent　level　(PCI　=　92),　we　recommend　the　micro-surface　treatment.　This　study　will　be　important　for　pavement　maintenance　management　and　provides　a　reference　for　decision-making　and　implementation　of　preventive　maintenance　treatments.　©　ASCE.