Developing green and efficient microbial fertilizers is crucial for addressing the contradiction between nitrogen demand in maize growth and environmental pollution from nitrogen fertilizer application, thereby promoting crop growth and green agriculture. A single-factor pot experiment with fertilizer was carried out using Yuhe9 maize as the test material. The results showed that when 50% algal fertilizer replaced urea（T₃ treatment）, the aboveground dry weight of maize increased by 125% compared with that of the control, which was not significantly different from that of the full urea treatment, and it could replace 50% urea to achieve equivalent nitrogen supply. Anabaena azotica can increase soil inorganic nitrogen, total nitrogen content and nitrogen accumulation, improve soil pH, improve soil structure and organic matter content, with the highest alkaline dissolved nitrogen content in T₃ treatment, and soil organic matter content in T₂ treatment（full algal fertilizer） was elevated to 71.65 g/kg, which was 39.56% higher than the control. Algal fertilizer also significantly increased soil urease, catalase and nitrate reductase activities. Therefore, nitrogen-fixing Anabaena azotica algal fertilizer has significant potential in promoting maize growth and improving soil fertility, and is an effective microbial fertilizer.