We measured the complex permittivities of whole blood and blood plasma in quasi millimeter and millimeter wave bands using a coaxial probe method. The validity of these measurements was confirmed by comparing with those of a different measurement method, i.e., a dielectric tube method. It is shown that the complex permittivities of the blood samples are similar to those of water in quasi millimeter and millimeter wave bands. Furthermore, the temperature dependences of the complex permittivities of the samples were measured.