This paper first explains the research on the digital economy to optimize the resource allocation of the Xi’an high-tech manufacturing industry. Secondly, the evaluation index system for the digital economy and Xi’an manufacturing industry is constructed, and the weight of secondary indexes is determined using the entropy weight method. Then, a mediating effect model is constructed to determine explanatory variables, core explanatory variables, mediating variables and control variables according to the purpose of the study, and the mediating effect and impulse response are analyzed. The results show that, in terms of mediating effect, the level of digital economy development significantly positively impacts transaction size, infrastructure, and digital applications. In terms of the impulse response, when the digital economy variables generate a standard deviation shock, the response value of Xi’an’s high-quality manufacturing development is zero in the current period, reaches the maximum response value in the third period, and this positive effect gradually decreases in the fourth period and beyond but always maintains a positive development trend.