Calcium, magnesium, and sulfur are secondary macronutrients to support crop’s growth after nitrogen, phosphorus and potassium. The study aimed to find out the optimum dose of CaO-MgO-S fertilizer for shallot in alluvial soil. Split plot experimental design and three replications were used. The main plot was two varieties of shallot, ‘Bima Curut’ and ‘Bangkok’. The sub-plot was the rate of CaO-MgO-S fertilizer, which consists of nine combinations. The ranges of the rates were CaO: 0-225 kg ha-1, MgO: 0-100 kg ha-1, and S: 0-100 kg ha-1. The result showed that there were no significant differences between the treatments on shallot bulb yield. ‘Bima Curut’ and ‘Bangkok’ showed the same responses to the treatments. The application of CaO-MgO-S fertilizer did not increase the shallot growth, nutrient uptake and shallot bulb yield significantly. However, giving 75 kg of Ca ha-1, 50 kg of Mg ha-1, and 50 kg of S ha-1 increased the fresh bulb yield by 20% than control.