A field experiment was conducted during Rabi season of 2011-12 at Madurai to study the effect of brown manuring on weed dynamics, yield and yield attributes and economics of irrigated maize. The weed management practice of PE alachlor 1.0 kg/ha + brown manuring proved to be effective in registering the lowest weed density of grasses, sedges, broad-leaved weeds and total weeds at 20, 40 and 60 days after sowing (DAS) and was at par with PE alachclor 1.0 kg/ha + daincha as intercrop with in-situ incorporation on 35 DAS except at 20 and 40 DAS. The above said prominent treatment has also registered higher weed control efficiency (84.41, 92.15 and 89.65% at 20, 40 and 60 DAS, respectively). As a result, the above promising treatment   has  increased  the  yield attributes such as cob length (17.09 cm), no. of rows/cob (14.76), no. of grains/row (38.56) and 100-grain weight (23.57 g), which in turn reflected   in    registering  higher grain yield of  7,227 kg/ha and stover yield of 11,563 kg/ha. The net returns ( 45,993/ha) and benefit cost ratio (3.61) were also more in PE alachlor 1.0 kg/ha + Brown manuring. The weed management practice of PE alachlor 1.0 kg/ha + daincha as intercrop with in-situ incorporation on 35 DAS was found to be the next best treatment in recording the higher grain and stover yield and economic returns.