The study uses the Taguchi method, analysis of variance (ANOVA), and principal component analysis (PCA) to design the optimal parameters of different quality characteristics on the continuous process of electrospun nanofibrous yarn. In recent years, the development of nanofibrous yarn has focused on the technique of electrospinning. In the study, the experiment is designed by a Taguchi L-9(3(4)) orthogonal array. Taguchi method is a unique statistical method which can efficiently evaluate optimal parameters and the effects of factor on quality characteristics. The experimental results obtained by the method are more accurate and objective than one-factor-at-a-time experiments. The discussed control factors are the concentration of the solution, nozzle size, flow rate, and take-up velocity. The considered quality characteristics are fiber diameter, fiber uniformity, and fiber arrangement. The optimum parameters of different quality characteristics are obtained through the main effect plot of signal-to-noise ratios (S/N ratios), then ANOVA and confidence intervals (CI) are applied to prove the results are reasonable. The multiple quality characteristics are analyzed by PCA through the normalized S/N ratios and principal component score. According to the experiments and analysis results, the optimum parameters for multiple quality characteristics are a concentration of 6 wt.%, nozzle number of 26G, flow rate of 3 m//hr, take-up velocity of 100 cm/min.