To verify the correctness of a research result, more than two kinds of independent method are often needed to examine or calculate the same physics quantity. The carrier concentration in both n-type ZnSe:Cl and p-type ZnSe:N crystal films is evaluated with Hall and C-V technique, as well as far infrared spectrum technique. It is found that the experiment data obtained with these two kinds of way coincide well with each other. Therefore, we can confirm the ZnSe, a widegap semiconductor material for blue/green light emitting devices, of high doping level.