Chemical preservatives are challenging to incorporate in bakery products due to the unpleasant smells and bitter tastes. Natural preservatives like spices, such as onion, fenugreek, and mustard, are used to enhance sensory and shelf life in the bakery industry. Therefore, the aim of this study was focused on the application of onion paste on the dough for enhancing the shelf life and sensory properties of bread. The onion was peeled and crushed using a miller. The obtained onion paste was blended with wheat dough in five levels (B0(0%), B1(4%), B2(8%), B3(12%), and B4(16%)). The bread samples were tested for appearance, crust color, aroma, taste, and overall acceptability, by a panel of ten untrained judges on seven-point hedonic scales. The results showed that the optimum blending ratio of the onion paste and wheat dough during the bread-baking process should be considered. In the treatment, B2(8%) is most effective in organoleptic (sensory) quality and with medium antimicrobial activity. The mean value of aroma and taste significantly increased from B0(0%) to B2(8%). The optimum value of the microbial count (7.61) after 6 days storage time was recorded in the treatment of B4(16%). From this work, it can be concluded that the onion paste with optimum amount can be used to preserve and enhance sensory quality.