Dynamic covalent chemistry would represent a novel strategy to disperse two-dimensional nanoparticles in base oil and thus enable the facile preparation of green lubricant nanoadditives that exhibit enhanced lubricating properties. In this work, a series of polymer−COF composites have been created in situ in base oil by use of transesterifications of phenylboronic ester functionalized block copolymers with (3-aminopropyl)-triethoxysilane-containing COF-1 (APTES-COF-1) via dynamic B−O covalent bonds. The COF based composites obtained with diblock and triblock copolymers can be colloidally stabilized in base oil as micellar aggregates with a APTES-COF-1 core and oleogel networks crosslinked by APTES-COF-1, respectively. These sulfur- and phosphorus-free lubricants exhibit excellent friction- (up to 50%) and wear-reducing properties (up to 94%) and superb load-bearing capacity of up to 1200   N. Such COF-enhanced loads were comparable to those achieved by MoS 2 nanosheets, sulfur- and phosphorus-containing lubricant additives. The enhanced lubricity originates from the in situ formation of nanoscale protective tribofilms including B 2O 3, h-BN, and β-SiC nanoparticles at the frictional interfaces. The present strategy of integrating block copolymers and COFs via dynamic covalent chemistry establishes a versatile platform for developing eco-friendly lubricants with exceptional tribological performance.