The　boundary　lubrication　behavior　of　Cu　nanoparticles　in　n-hexadecane　was　investigated　under　different　loads　by　experiments　and　simulations　herein.　Boundary　lubrication　model　with　sinusoidal　rough　peaks　was　established.　The　density　distribution　of　the　lubricant　along　the　film　thickness　with　and　without　Cu　nanoparticles　were　simulated　at　different　loads　using　MD　respectively.　The　shear　velocity　in　the　opposite　direction　was　applied　to　the　upper　and　lower　solid　walls　of　the　system,　and　the　stress　between　the　wall　atoms　and　the　copper　particle　atoms,　the　friction　force　of　the　solid-liquid　interface,　the　normal　pressure　and　the　friction　coefficient　were　calculated.　The　friction　coefficient　of　the　lubricant　containing　nano-copper　particles　was　measured　with　a　micro-nano　scratch　meter.　The　results　show　that　the　base　oil　n-hexadecane　in　the　two　lubrication　systems　is　stratified　under　different　pressures.　There　arc　still　a　small　amount　of　n-hexadecane　molecules　at　the　contact　interface　when　the　nano-rough　peaks　are　directly　contacted,　and　the　arrangement　direction　of　the　molecular　main　chain　is　the　same　as　the　shear　direction.　Cu　nanoparticles　may　reduce　the　maximum　stress　of　solid　wall　by　35.3%　and　improve　the　bearing　capacity　of　lubrication　system　at　200　MPa.　The　lubricating　oil　film　of　lubrication　system　without　Cu　nanoparticles　breaks　at　50　MPa,　while　that　of　lubrication　system　with　Cu　nanoparticles　breaks　at　200　MPa.　The　friction　coefficient　of　two　lubrication　system　under　boundary　lubrication　is　simulated,　which　is　in　accordance　with　the　experimental　measurement.　©　2023　China　Mechanical　Engineering　Magazine　Office.　All　rights　reserved.