Field experiments were conducted during the 2015 and 2016 cropping seasons at the Teaching and Research (T & R) Farm of the College of Agriculture, Kwara State University, Malete, to determine the effect of cropping patterns on weed infestation, growth and yield of a maize/soybean intercrop in the southern Guinea savanna of Nigeria. The experiments consisted of six treatments as follows: one row of maize alternated with one row of soybean (1:1), one row of maize alternated with two rows of soybean (1:2), two rows of maize alternated with one row of soybean (2:1), two rows of maize alternated with two rows of soybean (2:2), sole maize (1:0) and sole soybean (0:1). The treatments were laid out in a randomized complete block design with three replicates. Data collected were subjected to analysis of variance and means were separated by the least significant difference (LSD) at the 5% level of probability. Results showed that sole soybean consistently suppressed weeds and resulted in a higher yield. Similarly, the 2:1 ratio of maize to soybean did not only reduce weed density, it produced significantly higher yields of maize and lower yield of soybean, and had the higher land equivalent ratio and economic returns followed by sole maize.