Jiuzhaigou's ecological and geological environment was severely damaged after the 8.8 earthquake, and the engineering trauma formed by disaster prevention and control can realize landscape restoration through ecological restoration. To explore the interactions among soil microbial communities, vegetation characteristics, and soil physicochemical factors, as well as their response relationship with the number of years of restoration, we selected a typical steep-lying engineering wound in the high-elevation area of Jiuzhaigou (2082–2545 m) as the research object after 2—6 years of restoration. High-throughput sequencing of soil bacterial 16S rRNA and fungal ITS genes, combined with soil physical and chemical properties and vegetation characterization, and Partial Least Squares Path Model (PLS—PM) were used to investigate the synergistic effects of soil physical and chemical properties, plant communities and soil bacterial communities over the years of restoration. The results showed that the diversity and abundance of soil bacterial communities were gradually restored with the increase of restoration years, while the soil physicochemical properties and vegetation restoration effect were gradually close to the natural state. The ammonia nitrogen content of Laohuhai slope (LBP—5) increased from 35.1% to 213.8% compared with the area restored for 2–3 years, and there was no significant difference with the control TR. The differences in plant diversity, evenness, and dominance between the Pinganqiao slope (PAQ—6) and TR were not significant. PLS—PM analyses showed that restoration age and plant diversity significantly affected the relative abundance and community composition of bacterial dominant phyla, while the effect on the fungal community was small. The path coefficients of restoration age on both plant diversity and bacterial diversity were 0.449, and the path coefficient of plant diversity on bacterial diversity was 1.063, which had a significant positive effect, and there was a significant synergistic effect among plant, soil, and bacterial communities.