Weeds are the main obstruction under drill-seeded rice system so that two field experiments were conducted at the experimental farm of Rice Research & Training Center, Sakha Agricultural Research Station, Kafrelsheikh, Egypt in the summer seasons of 2020 and 2021 to reset the best chemical control program against grassy weeds in drill-seeded rice (Giza 179 cv.). Randomized Complete Block Design (RCBD) with three replications was used during both seasons of study. Ten chemical weed control were applied; (1) pendimethalin 50% EC (2.023 kg ai ha^-1) at 4 DAS as pre-emergence herbicide, (2) pendimethalin as per-emergence followed by (fb) penoxsulam 2.5% OD (0.0238 kg ai ha^-1) at 15 DAS as post-emergence herbicide, (3) pendimethalin as per-emergence fb bispyribac-sodium 2% SL (0.0381 kg ai ha^-1) at 25 DAS, (4) pendimethalin as pre-emergence fb ready mix of cyhalofop-butyl 7% + quinclorac 10% OD (0.238+0.1667 Kg ai ha^-1) at 20 DAS, (5) pendimethalin as pre-emergence fb fenoxaprop-ethyl 7.5% EW (0.0625 kg ai ha^-1) at 40 DAS, (6) thiobencarb 50% EC (3.57 kg ai ha^-1) at 4 DAS as pre-emergence herbicide fb bispyribac-sodium, (7) penoxsulam fb bispyribac-sodium, (8) penoxsulam at 15 DAS fb ready mix of cyhalofop-butyl 7% + quinclorac 10% OD at 25 DAS, (9) penoxsulam at 15 DAS fb fenoxaprop-ethyl  and (10) tank mix of penoxsulam (0.0119 kg ai ha^-1) + fenoxaprop-ethyl (0.0357 kg ai ha^-1) at 35 DAS as compared to un-treated plots (weedy check) and weed free. The obtained results showed that, sequential application of pendimethalin 50% at 4 DAS pre-emergence herbicide followed by fenoxaprop-ethyl 7.5% at 40 DAS or ready mix of cyhalofop-butyl 7%+quinclorac 10% at 20 DAS recorded the lowest density and biomass of grasses and highest weed control efficiency, highest rice vegetative growth, grain yield and its attributes and reduced yield losses to 3.2 and 3.9%, respectively as compared to weed free during both studing seasons. Based on the obtained data, it could be concluded that sequential application of pre-emergence fb post-emergence herbicides was the best in grassy weed management and improved rice grain yield (87.1% and 9.203 t ha^-1), while sequential application of early post-emergence fb late post-emergence herbicides ranked second (83.2% and 8.011 t ha^-1) and exceeded single application of pre-emergence herbicide (40.3% and 4.317 t ha^-1)  and post-emergence herbicide tank mix (72.6% and 7.351 t ha^-1) under dill-seeded rice conditions.