In order to develop the suitable planting mode of maize in red soil dryland, improve the related plant and ear characters of maize, promote high quality and high yield, and improve economic benefits. The experiment was conducted in the Science and Technology Park of Jiangxi Agricultural University from May 13, 2020 to October 18, 2020 and from May 5, 2021 to October 7, 2021. Taking maize as the control, three intercropping treatments of maize intercropping soybean, maize intercropping peanut and maize intercropping sweet potato were set up to compare their effects on agronomic characters such as plant height, stem diameter and ear width of maize and yield. The results showed that the plant height and ear height of maize intercropping soybean reached the maximum in two years, with plant height of 208.9 cm and 191.9 cm, ear height of 80.2 cm and 58.4 cm, respectively. The ear length and grain number per row of intercropping treatment were better than that of monoculture treatment. The ear length of maize intercropping and soybean reached the maximum, which were 16.5 cm and 19.0 cm respectively, and the grain number per row was also higher than that of other treatments. The yield of maize intercropping soybean was the highest, 42.1 kg and 43.5 kg respectively in two years. Compared with monoculture, intercropping can improve stem diameter, ear height, ear length, grain number per row and other ear traits, so as to improve corn yield, among which maize intercropping soybean is the best. The results of grey correlation showed that ear length and plant height had a great influence on maize yield. The comprehensive analysis shows that the use of maize intercropping soybean model is conducive to achieve high quality and high yield.