Weeds pose a major challenge to the adoption of conservation agriculture (CA), where reduced tillage and crop residues can limit the effectiveness of pre-emergence herbicides, highlighting the need to evaluate herbicides post-emergence application (PoE) option for summer greengram. A two-year field study was undertaken with an objective to assess the effect of eleven weed control treatments on weed density, crop productivity, and profitability of summer greengram under CA. The weed control efficiency declined over time from 30 to 50 days after sowing (DAS) due to weed biomass buildup. Among tested treatments, imazethapyr + imazamox 70 g/ha PoE at 20 DAS caused the best weed suppression, higher (nearly double) greengram seed yield, economic return, and benefit-cost ratio (2.08–2.53), compared to untreated control. The quizalofop was effective against grassy weeds, while higher rates of imazethapyr and sodium- acifluorfen + clodinafop showed limited efficacy. It is concluded that imazethapyr + imazamox at 70 g/ha PoE is the most effective and economical solution to manage weeds in summer greengram under CA.