A design of metal-dielectric non-polarizing beam splitter in a cube is proposed, using the needle optimization. The digital simulations of the splitter′s reflectance and reflection-induced retardance are presented. The effects of incident angle on the splitter′s performance are analyzed. Both amplitude and reflection-induced retardance of the splitter meet the requirement ignoring the phese of transmitted light. The differences between both components and the reflectance target which is 50% are less than 0.22%. The reflection-induced retardance is less than 0.29° in the range of 540~560 nm with the incident angle of 45°. When the incident angle deviates with the error of 1°, the reflectance of both components is influenced slightly and the reflection-induced retardance strongly depends on the incident angle.