Abstract: Applying organic fertilizers and amendments to soil is an important measure to improve soil structure, increase soil organic matter content and improve soil fertility. However, how the application of organic fertilizers and amendments affects soil ammonia (NH₃) emissions remains unknown. Exploring the effects of different fertilization treatments on soil NH₃ emissions is of great significance to reducing nitrogen (N) loss and protecting the ecological environment. Based on a micro-plot experiment of tomato greenhouse, a LGR915-0016 ultra-portable NH₃ analyzer was used to observe the characteristics of soil NH₃ emission under different fertilization treatments (50% chemical fertilizer N + 50% organic fertilizer N + amendment, HYG; 50% chemical fertilizer N + 50% organic fertilizer N, HY; 100% organic fertilizer N, Y; 100% chemical fertilizer N, H; and no fertilizer, CK). The results showed that the change trend of NH₃ emission flux of greenhouse soil under different fertilization treatments was basically the same during the growth period of tomato. Compared with the CK treatment, the H and HY treatments increased the cumulative NH₃ emission by 11.76% and 12.03%, respectively. The Y and HYG treatments significantly reduced the cumulative NH₃ emission by 24.31% and 15.20% relative to the CK treatment, respectively. Linear regression analysis revealed that soil NH₃ emission flux under different fertilization treatments was significantly related (P < 0.05) with soil temperature at 0-10 cm depths. There was a significant quadratic regression relationship (P < 0.05) between NH₃ emission flux and soil moisture content at 0-10 cm depth under different fertilization treatments. Compared with the single factor model, the two-factor model of soil moisture and temperature at 0-10 cm depth (R² was 0.7006-0.8497) better explained the changes in soil NH₃ emission flux. The total amount of NH₃ emission was extremely significantly (P < 0.01) correlated with soil NH₄⁺-N content, nitrate N content, pH and soil porosity at 0-20 cm soil depth, and was significantly correlated with soil bulk density at 0-20 cm soil depth. The cumulative contribution rate of the two principal components extracted by PCA analysis was 83.09%. Therefore, NH₃ emission in greenhouse soil was affected by different fertilization treatments. Considering soil NH₃ emission and its influencing factors, it is recommended to apply 100% organic fertilizer to reduce NH₃ emission of greenhouse soil.