This article experimentally investigates the buckling strength of carbon fiber-reinforced polymer laminates. Samples were made with 16 layers of carbon fibers in four orientations of 0°, 30°, 60°, and 90°. Nano silica (SiO 2 ) and nano clay were used as fillers for enhancement of the buckling strength of carbon fiber-reinforced polymer laminates. The Taguchi method was used for design of experiments and optimizing the three input factors: nano silica, nano organoclay, and carbon fiber orientation. From the results, first, it was found that the most buckling strength belonged to the samples with the fiber orientation of 0°and the minimum strength belonged to the composite laminates with the 90°orientation of carbon fiber. Second, the use of two nano fillers in quaternary laminates (epoxy/carbon fiber/silica/clay) has increased the buckling strength of laminates about 45.5% and 22.5% in comparison with binary and ternary laminates, respectively. The binary laminates were made from carbon fiber/epoxy resin and the ternary laminates included carbon fiber/clay/epoxy. Third, the elastic modulus of laminates increased with an increase in the nano SiO 2 content. The most effective parameters according to the analysis of variance results were as follows: carbon fiber orientation, nano silica, and nano organoclay, with a probability value of 99%, 95%, and 90%, respectively. Finally, the analytical analysis was done according to the classical laminated plate theory for obtaining the buckling force and verifying and comparing the results with experimental buckling tests. The results obtained from classical laminated plate theory for two certain laminates were in excellent agreement with those obtained from experimental results.