In this thesis, we study color uniformity of white light LEDs with different package types. Based on the YAG phosphor model, we analyze the angular correlated color temperature deviation (ACCTD) for white light LEDs with different package types and find out which one is lowest. After that, we modify the ACCTD of specific package types with the same correlated color temperature by changing the structure of the package. Finally, we study the ACCTD changes in mid-field region for white light LEDs and define the distance of quasi far-field in color.