In recent years, walnut (Juglans regia L.) has become one of the state strategic economic tree species. However, although traditional soil management practices, such as intensive agriculture and deep tillage, are both time- and energy-consuming, they are still used in most walnut orchards. Therefore, it is imperative to develop a simple and effective soil management strategy to replace traditional practices. In the present study, we investigated the ecological effects of within-row mulching in soil microsites, which has been very popular in both Japan and America, and established an effective soil management practice in walnut orchards. Precocious ‘Lvling’ walnut trees in full fruit were used as trial materials, and soil ecological conditions, such as soil moisture, soil aeration, mineral nutrition, and three kinds of microflora (bacteria, fungi, and actinomyces), were studied in response to continuous within-row mulching. In the 2014 growing season, we found that the variation coefficients of soil water content of the 0-20 cm layer of soil mulched with dairy manure, wood chips, alfalfa, and control (non-mulching) were 9.27%, 10.27%, 12.15%, and 13.29%, respectively, and the maximum amplitudes were 1.86%, 1.95%, 2.17%, and 2.63%. Meanwhile, the average water contents of the 20-40 cm soil layer were 13.23%, 12.46%, 11.77%, and 11.43%, and the maximum amplitudes were 1.58%, 1.61%, 1.71%, and 2.44%, whereas the variation coefficients were 7.96, 9.49, 9.70, and 11.11%. In addition, continuous within-row mulching reduced the maximum amplitudes and variation coefficients of soil water content, which indicated that the soil moisture was more stable. The soil bulk densities in the 0-60 cm soil layer were 1.34, 1.38, 1.43 g/cm³, and 1.48 g/cm³; the total porosities were 37.62%, 36.19%, 35.29%, and 29.03%; and the maximum water capacities were 752.40, 723.80, 705.87, and 580.67 t/hm². In addition, the density of three kinds of microflora (bacteria, fungi, and actinomyces) were 430.94×10⁴, 208.87×10⁴, 183.42×10⁴ cfu/g, and 160.46×10⁴ cfu/g, in soils mulched with dairy manure, wood chips, alfalfa, and control (non-mulching), respectively; the Shannon-Wiener indices were 0.62, 0.58, 0.41, and 0.30; and the Simpson's diversity indices were 0.24, 0.21, 0.13, and 0.09. Therefore, our findings indicated that both soil aeration and microbial diversity were improved by mulching. Principal component analysis further indicated that the comprehensive scores of soil fertility with mulching dairy manure, wood chips, alfalfa, and control (non-mulching) were 0.61, 0.26, 0.09, and -0.96 and that the comprehensive effect order of the various fertility factors on soil fertility level was: organic matter > total N > total K > total P > water content > soil porosity > bacteria > fungi > actinomyces > soil bulk density. Therefore, the present study demonstrates that within-row mulching is beneficial to the development of soil microsites and that dairy manure was the most effective among the three mulching materials investigated, followed by wood chips and alfalfa, respectively. However, in the long-term, the effects of within-row mulching remain unclear and require further investigation.