Two factors are of great importance to the overall performance and efficiency of a fluid distributor: uniform distribution and dead zone volume inside the cavity. From the perspective of improving uniform distribution and reducing dead zones, this research optimized the design of a commonly-used fluid distributor with one side inlet, eight outlets, and a cylinder cavity through numerical simulation. For equal-distribution, results demonstrated that after the inlet diameter was fixed, the distribution became equal continuously with the decrease of the outlet diameter. In addition, compared with one-side-inlet fluid distributor, two-side-inlet fluid distributor and middle-inlet fluid distributor promoted the uniformity of fluid distribution greatly. This study also reported that fluid distributor with an outlet angle of around 30° increased equal-distribution mostly compared with other angles. For dead zones inside the distributor cavity, the conical cavity reduced dead zones significantly compared with the fluid distributor with cylinder cavity. However, for the design of a fluid distributor, it is necessary to make a compromise between improving equal-distribution and reducing dead zones, therefore two optimized fluid distributors combining configurations proposed above were designed. Numerical simulation results illustrated that new fluid distributor designs promoted distribution among outlets more uniformly and reduced dead zones inside the distributor cavity tremendously.