Abstract: Intercropping of maize and soybean is widely practiced in the northern China. A 2-year field experiment was conducted to investigate the effect of intercropping patterns on dry matter accumulation and yield components of maize and soybean. Results indicated that there was no significant difference in dry matter of single maize for different planting patterns during earlier growing stage (before 79 DAS). During later growing period, there was very significant difference between biomass per plant of 1:3 intercropping (treatment I1) and sole maize, and significant difference between dry matter per plant of 2:3 intercropping (treatment I2) and sole maize. There was also significant difference between dry matter of individual plant of 1:3 intercropping and 2:3 intercropping. There was no significant difference in dry matter of single soybean for different planting patterns during whole growing season. Dry matter accumulation of single maize and soybean was fitted with Logistic equation for the intercropping and monocultures, correlation reached very significant level (P<0.01). Dry matter accumulations in the intercropped maize organs were higher than that of the sole maize because of edge effect. There was little difference in soybean organs for different planting patterns. Comparing with the sole maize, the intercropped maize had higher translocation rate of dry matter. Translocation rate of dry matter of the sole soybean was slightly higher than that of the intercropped soybean. When compared to the maize and soybean in the monoculture, the intercropping (I1 and I2 treatments) increased total yield by 6% and 320%, respectively.