Field investigation was carried out during two consecutive years (2005-06 and 2006-07) at Kanpur to find out direct and residual effects of atrazine application with regard to weed growth and crop growth of maizegreengram cropping system. Manual weeding followed by earthing operation done at 20 days after sowing (DAS) prevented weed competition (85.98% WCE) resulting in higher values of growth attributes viz., plant height 30.99%, culm girth 36.81%, leaf area index 76.19%, dry weight of plant 41.55% and crop growth rate 37.63% than weedy check which recorded lowest values of growth characters. Atrazine 0.50 kg/ha showed at par results with two manual weedings done at 20 and 40 DAS. Atrazine applied in maize had no residual effect on weed emergence and crop stand of succeeding greengram