Coconut milk protein (CMP) is a naturally derived protein recovered from the kernel of fresh coconut (Cocos nucifera L.) having a high nutrient value. With increasing demand of naturally available efficient emulsifiers and stabilizers for the production of food and health care emulsions with reasonable stability, many emulsifiers are being utilized for the commercial production of many products. Even though the CMP is reported as a poor emulsifier, we prepared very stable emulsions with CMP using sonication. The effects of ultrasound (250 W, 20 kHz and 120 W, 20 kHz) on the stability of sunflower oil-in-water emulsions made by CMP are studied. It is found that though the acoustic energy is responsible for further reduction of droplet size for CMP emulsions, energetic cavitations and high pressure shock waves, generated due to the collapsing bubble, are responsible for droplet breakup. The size of the dispersed droplets, in the case of sonication using an ultrasonic horn with all the concentrations of CMP, was smaller than that created using an ultrasonic bath. Emulsions sonicated by the ultrasonic horn were found to be very stable with variation of salt concentration.