Adding　nanoparticles　can　significantly　improve　the　tribological　properties　of　lubricants.　However,　there　is　a　lack　of　understanding　regarding　the　influence　of　nanoparticle　shape　on　lubrication　performance.　In　this　work,　the　influence　of　diamond　nanoparticles　(DNPs)　on　the　tribological　properties　of　lubricants　is　investigated　through　friction　experiments.　Additionally,　the　friction　characteristics　of　lubricants　regarding　ellipsoidal　particle　shape　are　investigated　using　molecular　dynamics　(MD)　simulations.　The　results　show　that　DNPs　can　drastically　lower　the　lubricant＇s　friction　coefficient　μ　from　0.21　to　0.117.　The　shearing　process　reveals　that　as　the　aspect　ratio　(α)　of　the　nanoparticles　approaches　1.0,　the　friction　performance　improves,　and　wear　on　the　wall　diminishes.　At　the　same　time,　the　shape　of　the　nanoparticles　tends　to　be　spherical.　When　0.85　≤　α　≤　1.0,　rolling　is　ellipsoidal　particles＇　main　form　of　motion,　and　the　friction　force　changes　according　to　a　periodic　sinusoidal　law.　In　the　range　of　0.80　≤　α　＜　0.85,　ellipsoidal　particles　primarily　exhibit　sliding　as　the　dominant　movement　mode.　As　α　decreases　within　this　range,　the　friction　force　progressively　increases.　The　friction　coefficient　μ　calculated　through　MD　simulation　is　0.128,　which　is　consistent　with　the　experimental　data.　©　The　Author(s)　2024.