The long-term field experiment consisted of three planting patterns, i.e., monoculture maize (MM), monoculture soybean (MS), and maize-soybean relay strip intercropping (IMS), and three application rates of total nitrogen, i.e., no nitrogen (NN), reduced nitrogen (RN) of 180 kg N ha-1, and conventional nitrogen (CN) of 240 kg N ha-1. The compact maize (Zea mays L. cv. Denghai-605) and shade-tolerant soybean (Glycine max L. cv. Nandou-12) were used as experimental crops. Maize was sown on April 1, 2012, April 3, 2013, and April 5, 2014; and harvested on July 29, 2012, August 1, 2013, and August 2, 2014, respectively. Soybean was sown on June 10, 2012, June 11, 2013, and June 15, 2014, with simultaneous application of maize topdressing and soybean base fertilizer; and harvested on October 31, 2012, October 29, 2013, and October 26, 2014, respectively.