Powder flow is an important factor in the production of tablets and capsules. Each ingredients (in the form of powder) has its own flow and must be taken into account in the manufacturing process design. Different particles have different sizes, shapes and density. In determination of powder flow, these three factors will affect the flow ; hence they are considered as the parameters in the experiment to investigate and determine the best size of the particles which will have the fast powder flow. The diameter of hopper orifice is also the factor that can affect powder flow; therefore it is also taken into consideration as the parameter that can affects the powder flow.