Tillage practices can change the soil environment (including soil properties and enzyme activity) and the rhizosphere microbial community, thereby inducing changes in root growth and the nutrient uptake capacity. This study was carried out on a long-term (since 1983) tillage field experimental platform. It aimed to explore the effects of tillage practices and growth stages on maize root development, soil properties, and the rhizosphere microbial community. The results can provide a theoretical basis for the further analysis of crop–soil–microbial interactions. In our study, we investigated the abundance and diversity of the rhizosphere microbial community and their relationship with root growth characteristics and soil factors under long-term (since 1983) conventional tillage (CT), subsoil tillage (ST), and no-tillage (NT) practices using quantitative PCR and high-throughput 16S/ITS sequencing. In 2020, at the 30-days-after-silking (VT 30) stage, NT increased the root length, root dry weight, N accumulation, and N uptake rate of maize roots compared with CT by 16.7%, 16.3%, 41.9%, and 41.9%, respectively. In 2020, at the 12th leaf (V12) and VT 30 stages of maize, NT significantly increased the contents of soil total nitrogen (by 16.3% and 11.0%, respectively), total carbon (by 23.9% and 12.9%, respectively), soil organic matter (by 24.8% and 10.3%, respectively), and soil urease activity (by 5.5% and 5.6%, respectively) compared with CT. Moreover, NT significantly increased the bacterial and fungal abundances compared with CT. Redundancy analysis (RDA) showed that the variation in the microbial structure correlated markedly with the alteration in root indicators, soil properties, and enzyme activities. Long-term no-tillage improved the abundance and diversity of rhizosphere microbial communities by increasing the soil total nitrogen, total carbon, and soil organic matter, and promoted the N accumulation of roots and their uptake rate.