Abstract: This paper takes polylactic acid (PLA) as the matrix and basalt fiber (BF) as the reinforcement to prepare BF/PLA composites through injection molding. The influence laws of mechanical properties of polymers under different basalt fiber diameters, lengths, and content ratios are explored. Inspired by the Materials Genome Initiative, a prediction method for the mechanical properties of composites is proposed. Through experiments and data correlation analysis, it is found that the mechanical properties of the composites show a trend of increasing first and then decreasing with the increase of fiber diameter, length, and content. The analysis of variance method is used to determine the significance of the influencing factors of mechanical properties. Based on the F value, a normalization method for fiber parameter influencing factors is proposed, and a factor reduction fitting function for mechanical properties based on normalized variables is established to approximately predict the mechanical properties of composites. The determination coefficients R2 of each mechanical property prediction are all above 0.7, and the accuracy is within the acceptable range of engineering. Taking a certain real vehicle front bumper model as the verification object, a finite element model is constructed. The static strength and low-speed collision simulation results of the commonly used material PP-GF30 for the current bumper and the BF/PLA composite with a ratio of 13 μm-5 mm-35% are compared. The results show that under the static strength analysis condition, the maximum displacement value of the selected ratio composite is 10.7% lower than that of the PP-GF30 front bumper. Under the frontal collision, frontal offset collision, and 60-degree angle collision conditions, the maximum strain values of the selected ratio composite are 8.7%, 22.6%, and 31.8% lower than those of the PP-GF30 front bumper, respectively. The selected ratio composite has a higher strain resistance capacity than PP-GF30 under the same conditions.