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A three year study was conducted at the Regional Research Centre Mtwapa in Coastal Kenya from 1993 to 1995. The objective of the study was to investigate the effect of cowpeas planted in rotation with maize on weed and maize growth in the following season. Effect of tillage methods, weeding regime and time of planting were also investigated. There was a significant interaction (P 0.01) between tillage and rotation for stand counts in the three years of the study. This was due to plant residues left behind in the minimum tillage plots, which provided hiding places for the rodents, and insect's pests that destroyed the germinating maize seedlings. There was a significant difference (P 0.01) in ear height between the rotation treatments and a significant year by rotation and year by tillage interaction. Cowpea rotation resulted in a significant increase (P0. 05) in maize grain yields over the fallow plots. The weed biomass and weed types recorded were highly int1uenced by the type of tillage and rotation practiced. Commelina benghalensis dominated the conventional tillage plots while grasses and Oxygonum sinuatum dominated the minimum tillage plots. The weed biomass in the rotation plots was lower than the in the fallow plots and the weed seed production was lower in the former. The results of this work indicate that it is possible to reduce the weed load and also improve on soil fertility if cowpeas are planted in rotation with maize.