The trend of using alternative fuels has been on the boom to tackle fossil fuel depletion. The overuse of fossil fuels due to the rapid population and industrialization as well has led to the deficiency in fossil fuels. As a result, many alternative fuels have been found and have been in use as an effective replacement in terms of combustion and emission performance characteristics. However, the noise and vibration characteristics also have to be tested for ensuring the comfortability. This research paper discusses the importance and characteristics of noise and vibration of the taken test fuels. The test fuel was prepared from watermelon seeds that come under the category of biodiesel. Three biodiesel blends were prepared by mixing them with pure diesel such as WMB10% (90% of diesel + 10% of watermelon seeds biodiesel), WMB20% (80% of diesel +20% of watermelon seeds biodiesel), WMB30% (70% of diesel +30% of watermelon seeds biodiesel), and WMB0% (100% of pure diesel). The experimental tests were carried out in a single-cylinder, four strokes, naturally aspirated, water-cooled and direct injection (DI) diesel engine. Using different engines of 1000 rpm, 2000 rpm, and 3000 rpm, noise and vibration characteristics were measured. The load was maintained at 100% for all experimental tests. From the results, it was clearly found that the noise and vibration of higher proportioned biodiesel were lower, and the reduction was achieved at a significant level.