For　an　accurate　prediction　of　the　friction　experienced　by　the　linear　rolling　guide　and　the　factors　affecting　it,　the　fluid　lubrication　state　of　the　rail　was　considered,　and　the　effect　of　the　friction　of　the　linear　guide　on　the　ball　contact　angle　and　preload　was　studied　based　on　the　Hertz　contact　theory.　Based　on　the　Hertz　contact　theory,　the　static　equations　and　the　ball-raceway　contact　mechanics　equations　of　the　linear　rolling　guide　were　established　for　vertical　loading.　Using　the　Hertz　contact　theory,　changes　in　the　ball　contact　force　of　the　linear　rolling　guide　were　analyzed.　Combining　the　analysis　of　the　critical　load　and　the　oil　film　obstruction　between　the　balls　and　the　rail,　a　friction　model　was　established　for　studying　the　effect　of　the　external　load.　Experiments　were　carried　out　on　a　domestic　model　of　the　linear　rolling　guide　to　validate　the　developed　friction　model.　Through　the　analysis　and　comparison　of　the　experimental　and　theoretical　data,　the　influence　of　the　resistance　of　the　lubricating　oil　film,　the　contact　angle,　and　the　preload　on　the　friction　of　the　linear　guide　were　verified.　The　results　show　that　the　friction　of　the　linear　rolling　guide,　under　the　condition　of　lubrication,　is　affected　by　the　contact　angle　and　the　preload　force.　©　All　right　reserved.