Long-term fertilization with a combination of chemical fertilizer and maize straw positively affects the photosynthetic properties and yield of summer maize. The study found that using both fertilizers together leads to higher maize yield compared to using them individually. Chemical fertilizer application increases leaf area, leaf area index, and chlorophyll content, resulting in higher grain number and weight. Maize straw application alone or without any fertilization decreases chlorophyll content. The combined application of chemical fertilizer and maize straw enhances grain number, delays leaf aging, and prolongs leaf function, ultimately increasing summer maize yield. This combined fertilization approach is recommended for achieving high maize yields.