Composite solid propellants consist of two types of materials: solid and liquid. Solid ingredients include oxidizers, metal fuels, and additives, whereas liquid materials include fuel binders, curing agents, and plasticizers. To produce a composite solid propellant, all these ingredients are mixed homogeneously to make a propellant slurry, which is then poured into a molded tube. The process is known as the casting process. The casting process consisted of two stages: putting the slurry into the mold tube under vacuum conditions and then putting the mandrel into the tube before the propellant slurry solidifies. This conventional vacuum casting technique has limitations when applied to viscous propellant slurries due to the rheological behavior of the slurry. This research aims to enhance vacuum casting by incorporating vibration into the process. This technology allows the composite propellant slurry to fill the gap between the tube and the mandrel, making the molding process easier and more efficient and developing a propellant with extremely low porosity to achieve better mechanical properties.