Injection molding is an effective mass production technology for plastics parts. This molding technology can also be applied to mold metal and /or ceramics parts of complex geometry using powder-polymer binder mixing compound following de-bounding and sintering manner. Ceramics is considered as a potential material suitable for 5G transmission devices such as cellular phone housing. However, using ceramics powder injection molding (CIM) face a great challenge due to its ultrahigh viscosity, particularly for long and thin wall parts. To overcome this issue, supercritical fluid (SCF) was added to CIM, and the high fluidity property of SCF was used to improve the fluidity of traditional CIM materials in this study. By adding SCF, the injection pressure can be greatly reduced and the filling can be stabilized, which avoiding the defect of powder and binder separation or jetting. At the same time, combined with the gas counter pressure (GCP) technology can effectively suppress the fountain flow of the melt, which will improve the uniformity of the powder distribution again. Research results show that after adding supercritical fluid and GCP technology, the filling pressure can be greatly reduced by 15%, and the overall density uniformity is also greatly improved by 20%. The appearance of the product is better than traditional CIM, and it will be applicable to the development of thinner and lighter ceramic products in the future. Keywords: Ceramics-Powder Injection molding, Super Critical Fluid, Gas Counter Pressure, Uniformity of Powder Density