We tested the IP-BPM cold model using a network analyzer to check its design. The measured frequencies of two dipole modes agreed with the calculation within reasonable error in the calculation. Coupling of the output ports (Qext ) shows reasonable value for Y-port, but unexpected small value for X-port. We think that coincidence of an eigen mode frequency of wave guide part and the dipole mode of X-mode is the reason of the strong coupling in X-port.