The impact of road construction on typical steppes has garnered extensive attention in recent decades, due to the expansion of road networks and rapid urbanization. Yet, the specific effects of road class and distance on plant population growth remain unclear. Consequently, our study focused on the typical steppe of the Loess Plateau in eastern Gansu Province, examining the factors and mechanisms by which road construction (including road class and distance) influences the growth and reproduction of the dominant species Artemisia capillaris and the associated species Aster altaicus. Our findings indicate that road construction stimulates both the lateral growth and asexual reproduction in Artemisia capillaris, and the vertical growth and sexual reproduction in Aster altaicus. Further, Aster altaicus has a higher renewal potential. These two species exhibit higher aboveground biomass on highways compared to other road types (such as railways and expressways), which makes them more susceptible to the impacts of road construction. In addition, road construction has a significant impact on the proportion of aboveground biomass in the community by influencing the soil. There is a clear threshold for aboveground biomass and its proportion in the Aster altaicus at a distance of 20-35 m. Thus, it is imperative to integrate vegetation protection and restoration efforts within this range with adaptive road management to mitigate the effects on plant growth and reproduction and to guide the community assembly process, addressing the significant challenges posed by road construction to population and community dynamics.