To determine the optimal plant population density and weed management method in irrigated spring sown chickpea, an experiment based on RCBD arranged in a split plot with four replications was carried out at research farm of University of Tehran (karaj) during 2010-2011. Main factor comprised nine treatments, namely, 1) trifluralin pre-plant (960 g ai/ ha), 2) pendimethalin pre-plant (825 g ai/ha), 3) imazethapyr pre-emergence (70 g ai/ha), 4) imazethapyr post-emergence (40 g ai/ ha), 5) mechanical weeding, 6) pyridate (1200 g ai/ha) along with mechanical weeding, 7) pyridate post-emergence (1200 g ai/ha), 8) complete hand weeding (weed free check), and 9) weedy check (no weeding). Sub factor included three densities of 35, 45 and 55 plants per m2. Results revealed that plant density and weed management had significant effects on chickpea characteristics. The highest seed and biological yield obtained at 55 plants per m2; however it showed similar results for these traits at 45 plants per m2. The weed biomass was significantly differed at various plant densities and it was the lowest at 55 plants per m2. After complete weeding (weedy check), pyridate + mechanical weeding and pendimethalin controlled effectively weeds. After complete weeding, the pendimethalin gave the highest chickpea seed and biological yield at Karaj prevalent conditions.