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With the extensive promotion of controlled-release urea (CRU), its N-release pattern has been shown to match the crop's N-demand period and improve crop yield by reducing N losses. Nevertheless, the impacts of CRU on summer maize yield, especially on greenhouse gas emissions, have rarely been reported during its long-term use. It is necessary through long-term positioning field experiment with CRU application to investigate the regulatory mechanisms of maize yield formation, nitrogen use efficiency (NUE), ammonia volatilization and greenhouse gas emissions. The long-term fertilizer positioning experiment for ten years, four treatments were performed: polymeric-coated controlled-release urea (CRF, 42% N, 3-months controlled-release period), sulfur-coated controlled-release urea (SCF, 35% N, 3-months controlled-release period), common urea (CCF, 46% N) and no nitrogen fertilizer (CK). Results showed that the two coated controlled-release fertilizers significantly increased NUE and dry matter accumulation in summer maize, and ultimately improved grain yield. Compared to CCF, CRF and SCF treatments increased post-silking dry matter accumulation by 16.3% and 13.3%; NUE by 42.3% and 28.9%. The 2-year mean grain yield of CRF and SCF treatment increased 9.0% and 12.4% compared to CCF treatment. CRF treatment significantly increased the NO 3 --N content in 0–60 cm soil layer; while CRF and SCF treatments showed a significantly higher NH 4 +-N concentration in the 0–20 cm soil layer than CCF treatment. Compared to CCF treatment, the CRF and SCF treatments significantly reduced peak ammonia volatilization, and the average cumulative emissions of ammonia volatilization of two years were reduced by 80.8% and 53.2%, respectively. CRF treatment had lower peak of N 2 O emissions but longer N 2 O emission duration than other N application treatments. The two-year average cumulative N 2 O emissions from CRF treatment increased by 49.6%, and SCF treatment increased by 61.1% compared to CCF treatment. Compared to CK treatment, total cumulative CH 4 uptake was 36.1% lower in CRF treatment, 60.9% in SCF and 78.9% in CCF treatment. The higher cumulative N 2 O emissions from CRF and SCF treatment resulted in a significantly higher global warming potential (GWP) than CCF treatment. The two-year mean increase in greenhouse gas intensity (GHGI) was 36.2% for CRF treatment and 44.7% for SCF treatment compared to CCF treatment. Long-term application of coated controlled-release fertilizers could achieve high yields and nitrogen use efficiency. However, there is a risk of increased N 2 O emissions, causing elevated GHGI. In the future, it is necessary to strengthen the research on the comprehensive effects of long-term reduced application of CRU on crop yield and greenhouse gas emissions, in order to promote the wide application of environmentally friendly CRU in the field. [Display omitted] • Long-term application of CRU could achieve sustainable crop yield improvement. • Long-term application of CRU significantly reduced ammonia volatilization and CH 4 emissions. • Long-term application of CRU carried the risk of increased N 2 O emissions, leading to higher GHGI. [ABSTRACT FROM AUTHOR]