Machine transplanting technology is a critical approach for enhancing rice production efficiency and ensuring stable yield increases，with fertilization management being essential for seedling growth and emergence rates. This study investigated the effects of different types of nitrogen fertilizers on seedling emergence rate，seedling quality，root development，and rhizosphere soil nutrient content during the mechanized rice transplanting process. Hybrid rice varieties Yongyou 1540 and Huazheyou 210 were utilized in the experiment，different types of nitrogen fertilizers were employed，and various nitrogen application rates(250-750 mg/kg)were set up according to conventional seedling cultivation methods. The results showed that when applying ammonium sulfate，a pure nitrogen application rate of 250-500 mg/kg had no effect on rice seedling emergence rate，significantly improved the overall quality of the rice seedlings，and increased the root binding force of the seedlings. In contrast， applying urea significantly inhibited rice seedling emergence and root growth，resulting in an average decrease of 9.7% in emergence rate and 27.0% in root binding force. Compared with ammonium sulfate，urea significantly increased the accumulation of amide nitrogen in the rhizosphere soil，leading to toxicity. Overall，applying ammonium-type nitrogen fertilizers(ammonium sulfate)to rice seedling soil was more beneficial than amide-type nitrogen fertilizers(urea)for enhancing seedling emergence，seedling quality，and root binding force. Additionally，a pure nitrogen application rate of 250-500 mg/kg was recommended as the most suitable range.