Abstarct:   To produce polymer matrix composites, direct printing can be used without the need to make filament. This technology is known as liquid deposition modeling (LDM). In this process, polymer materials mixed with particles enter the printer cylinder in the form of granules and after reaching the melting temperature, they are printed on the bed of the machine. In this study, polymer matrix composites were printed using the solution method and the use of a 3D printing machine. Polypropylene was used as the baxse polymer and copper micro and nano powder in the sizes of 20, 45 micrometers and 40 nm as additives and xylene solvent was used to make the composite solution. In order to design the tests, the full factorial design (FFD) method was considered and the results were analyzed baxsed on the analysis of variance (ANOVA). The input variables for printing the samples are: laxyer thickness, micropowder size and weight percentage of micropowder, each of which was considered at two levels of 180 and 240 microns, 20 and 45 microns, 10 and 20% by weight, respectively. Samples containing nanopowder in 4%, 7% and 10% by weight were prepared and printed. The values of the coefficient of variation obtained from the ANOVA of the yield strength and the elongation percentage were equal to 98.85% and 98.63%, respectively. The yield strength of the samples containing micropowder increased by 54.26% compared to the raw sample. The values of elongation percentage of the samples containing micropowder decreased by 41.49% compared to the raw sample. The flexural strength and flexural modulus of samples containing micropowder increased by 15.08% and 24.79%, respectively, compared to the raw sample. The impact resistance of the samples containing micropowder decreased by 34.06% compared to the raw sample. The optimal combination of input variables to maximize the three objectives of yield strength, ultimate tensile strength and fracture strength using the desirability method are: laxyer thickness 180 micrometers, micropowder size 45 micrometers and weight percentage 10%. Also, the optimal combination of input variables for simultaneous maximization of flexural strength and flexural modulus and independent maximization of impact resistance are: laxyer thickness 180 micrometers, micropowder size 45 micrometers and weight percentage 20%. The results showed that the ultimate tensile strength and fracture strength of the sample containing 7% by weight of nanopowder increased by 6% and 9.5%, respectively, compared to the raw sample. The elongation percentage of the samples containing 4%, 7% and 10% by weight of nanopowder decreased by 37.31% compared to the raw sample. On the other hand, the flexural strength of the samples containing 4%, 7% and 10% by weight of nanopowder increased by 28.4% compared to the raw sample. Meanwhile, the impact resistance of the samples containing 4%, 7% and 10% by weight of nanopowder decreased by 23.24% compared to the raw sample.