The Melt spinning technique of Nano Zinc Oxide/PP/PLA composites filaments fabricated by plasma treated Nano Zinc Oxide（NZOP） was studied in the present investigation. The experimental results showed that the physical and mechanical properties of Nano Zinc Oxide/PP/PLA composites filaments depended on the following factors of the percentage of NZOP, the percentage of maleic anhydride (MAH), the plasma treatment parameters, helium gas flow rate, output power, sample treatment or stationary time and oxygen gas flow rate. Among them the oxygen gas flow rate had the significant influence on the filament properties of tensile modulus, the yield strength, the melting temperature and the crystallization temperature. Stepwise multiple regressions orthogonal design method of system optimization was used to determine the percent of contribution of each factor. It was found that the four indicators were different by these analyses. The experimental results indicated that the optimized conditions by stepwise multiple regressions were better than that by traditional analysis.