[Objective] Based on the analysis on benefit and loss of soil and water conservation for provincial roads construction projects in Weifang City of Shandong Province to evaluate the influence degree of soil and water conservation of the local provincial roads construction projects.[Methods] Taking 4 different highways(S220, S221, S321 and S327) in Weifang area as an example, the soil and water loss impact indices(SWⅡ) for four provincial roads construction projects were quantitatively analyzed and evaluated.[Results] The SWⅡ of S220, S221, S321 and S327 was 0.194 2, 0.158 8, 0.175 8 and 0.167 1, respectively, which was lower than the average SWⅡ value of national highway construction project in China. The results indicated that the impacts of soil and water loss caused by highway construction project in Weifang City were lower than the national average level. The main reason for the low SWⅡ in Weifang was that the average occupation land area(4.82 hm²/km) and influence extent(0.91 hm²/km) was smaller and the earth excavation and filling volume(5.06×10⁴ m³/km) and waste residue(400 m³/km) was less, the influence time was shorter (21 months) and the amount of soil and water loss(437 t/km) was less.[Conclusion] For different highway projects, to reduce their impacts on soil and water loss, the construction area and earthwork volume should be reduced. Specifically, by increasing the soil erosion conservation area can mitigate the impact of project construction on soil and water loss and can protect the eco-environment.