In the high lands of Ethiopia, weed causes considerable yield losses on wheat production due to absence of better management options for the producers. This also true, in the highlands of Guji Zone, Southern Oromia. Field experiment was conducted to study the effect of different Post-Emergence herbicides to Control wild oat and other grass weeds in wheat (Triticum aestivum L.) at Bore Agricultural Research Center on station and Ana Sora district on farm during 2015/16 cropping season to identify the most effective herbicide for the control of the targeted weeds thereby improving wheat production to the area. The Experiment was laid out in randomized complete block design using three replications. Pallas 45OD, Current 8EC, Ralon super144, hand weeding at tillering and weedy (check) were used as treatments. Based on the combined analyzed data result, significant variation was observed among treatments used for all of the parameters tested. Among the utilized herbicides, Pallas 45OD showed better control of wild oat and other grass weeds. In other cases, hand weeding and hoeing at tillering resulted in lowest weed density. Highest grain yield (4210.7 kg ha-1) was recorded in Pallas 45OD followed by Current 8 EC (4000.3 kg ha-1). Partial budget analysis of the study revealed that ,applying Pallas 45OD had the highest net field benefit (30591.9 ET birr) followed by Current 8EC(29512.3ET birr ha-1 compared to Ralon Super 144(26265.1ET birr ha-1),Three times hand weeding( 22911.6 ET birr ha-1) & weedy check(22919.4ET birr ha-1).However, Current 8EC had showed maximum economic profitability than Pallas 45OD and other types with marginal rate of return(MRR) of 6494.4%. Therefore, Current 8EC at rate of 1itre ha-1 is the best herbicide for the effective control of wild oat and other grass weeds in wheat under proper cultural practices and there by improve yield production of wheat up to 25.1% at high lands of Guji Zone, Southern Oromia. Key words: wheat, Herbicide, weed

Keywords: Obsa Chimdesa