A field experiment was conducted to study the effect of different sources and levels of sulphur on yield and yield attributes in onion under central dry zone of Karnataka at Zonal Agricultural and Horticultural Research Station, Babbur farm, Hiriyur. The experiment was laid out in Randomized Complete Block Design with nine treatments and three replications during 2019 – 20. Among different treatments, plants treated with RDF + sulphur @ 30 kg ha-1 through gypsum recorded maximum polar diameter, equatorial diameter, average bulb weight, bulb yield per plot, marketable bulb yield, total bulb yield, per cent A grade bulb yield, per cent B grade bulb yield.