This investigation was carried out at El-Gemmeiza Agricultural Research Station during two winter seasons of 2019/2020 and 2020/2021,to study the response of different onion transplanting dates (Giza 20; T1,15th of December;T2, 30th of December;T3,15th of January)for intercropping with different densities of faba bean (Giza716;D1,100%onion+25.0%faba bean; D2, 100% onion+33.5% faba bean;D3,100% onion+42.0 % faba bean of the recommended density) and its impact on yield and yield components of both crops.The competitive relationships and yield advantages was also studied.A split plot design with three replicates was employed.The results showed that early transplanting (e.g.,T2) had a good impact on onion growth, yield and its components,yet this was accompanied with a negative response on quality traits of yielded bulbs.The highest quality traits were achieved with late transplanting (T3).Obviously,the mean value of onion growth, yield and its components was increased with increasing sowing density of faba bean,except for plant height and weight of culls yield.T1 plus D1 was the best treatment for enhancing vegetative growth and yield components except for plant height and weight of culls yield,All faba bean studied characters possessed the highest mean value at middle density of faba bean was the best one as compared to D1 and D3 densities.The interaction released that T3 at D2 achieved the highest mean values for number of seeds, seed yield and seed yield.It has been concluded that, early transplanting of onion(15th of December)in association with light density of faba bean(25%)possessed the highest value in both seasons of LER, RCC, ATER, MAI and Income return.