Mixture of controlled release urea and urea one-application can synchronize the need of nitrogen requirement, postpone leaf senescence and increase yield for summer maize, coupling with labor saving, which will be the most effective way of nitrogen application in the future. In our experiment, two maize cultivars of different nitrogen efficiency were selected to study the effects of different ratios of controlled-release urea and urea on leaf senescence characteristics, soil inorganic nitrogen content, enzyme activity and yield of different maize varieties. Using cultivars YH988 and ZD958, which were mainly planted cultivars in Huang Huaihai Plain as test materials, 6 treatments (CK, N180U, N180C1, N180C2, N180C, and N300U) were set up, of which CK was no nitrogen treatment, 180 and 300 represented nitrogen application levels of 180 kg/hm² and 300 kg/hm², respectively. U stands for total urea treatment (basal nitrogen and top dressing was 2:3), C1 and C2 stand for the controlled release urea:ordinary urea being 1:2 and 2:1 (basal nitrogen one-application), and C stands for full controlled release urea treatment (basal nitrogen one-application). The results during 2018 and 2019 showed that one-off application of the blend of controlled release urea (CRU) and urea (U) before sowing at 180 kg N hm^-2 was able to satisfy the N demand of a summer maize system with varieties YH988 and ZD958 in Huang Huaihai Plain. One-off application a mixture of CRU and urea with 1:2 and 2:1 of cultivars YH988 and ZD958 at 180 kg N hm^-2 achieved the highest yield, which indicated N180C1 and N180C2, respectively. During the maize growth period, comparing with CK treatment, the superoxide dismutase (SOD) and peroxidase (POD) activities of ear leaves increased significantly and the membrane lipid peroxides (MDA) content of ear leaves reduced significantly in treatment N180C1 and N180C2 for cultivars YH988 and ZD958, respectively, while also increasing soil inorganic nitrogen content, urease and sucrose enzyme activity in the post-silking stage for summer maize. In summary, for the two maize cultivars with different nitrogen efficiencies, optimizing the mixture of controlled-release urea and urea can delay the senescence of functional leaves of maize through the complementary effects of the release of urea in the early stage and the release of CRU in the later stage, prolong the functional period, and increase the soil inorganic nitrogen content and enzyme activity in the later growth period. The treatments N180C1 and N180C2 are most suitable for YH988 and ZD958, respectively.