Vitamin D encapsulation can significantly improve its bioavailability, stability, and solubility. Various biopolymers viz. whey protein isolate, carboxymethyl cellulose, alginate and gum arabic were studied for their potential to be used as wall material and gum arabic was selected for encapsulating vitamin D3 as it possesses lesser particle size, apparent viscosity and better stability in terms of zeta potential. Box Behnken design was employed for optimizing the process conditions for developing vitamin D3 nanoemulsion. Box Behnken design was constructed using ultrasonic amplitude, sonication time and vitamin D3/wall material percent as independent factors. The optimum conditions obtained were ultrasonic amplitude (80 %), sonication time (12 min) and vitamin D3/wall material percent (5). The designed nanoemulsion showed a particle size of 20.04 nm, zeta potential of -28.2 mV, and encapsulation efficiency of 71.9 %. Chemical interactions were observed in the developed nanoemulsion as demonstrated by Differential scanning calorimeter thermograms and Fourier transform infrared spectra of the nanoemulsion. The Korsmeyer-Peppas model was the most suitable for describing the release of vitamin D3 from the nanoemulsion. Fabricated nanoemulsion has the potential to be used in food and pharmaceutical industries.