Onion (Allium cepa L.) is the most important commercial vegetable crop widely grown throughout the world. It is also animportant bulb crop in Ethiopia. However, its production and productivity are restricted by diferent factors, including biotic andabiotic stresses. Tis review investigates the potential impacts of spacing and varieties on onion yield and yield components inEthiopia. Countries around the world are producing onion for its nutritional value, medicinal properties, minerals, proteins, andcarbohydrates. In terms of production, onion ranks second only after tomatoes. Te average onion yield in Ethiopia is estimated tobe 8.8 tons/ha, while in the world, it is approximately 19.7 tons/ha. Inappropriate spacing and inadequate onion varieties are someof the limitations widely described for yield variation in Ethiopia. Tus, to control the size, shape, and yield of onion bulbs, spacingdetermination and variety improvement are some of the techniques currently employed in Ethiopia. Adama red, Bombay red, andred creole are some of the known varieties in the country, and the intrarow spacings for Adama red and Bombay red are reported tobe 4 cm and 6 cm, respectively. Diferent spacing between onion plants afects how much they produce and other factors such assize and quality, depending on the variety. It is important to assess whether changing spacing makes sense from both a farmingand economic standpoint, alongside considering other agricultural methods.