The research on the transverse impedance measurements of a linear induction accelerator cavity is psented. The device is transformed into coaxial (TEM) configuration by inserting two parallel off-axis wire conductors. Scattering parameters are measured using a network analyzer (HP8753D) with a computer as a controller. By comparing and colculating the shunt impedance is found. In order to eliminate the multiple reflection caused by nonmatched 50( coaxial transmission line to the beam pipe end, time-filtering is used. Analyzing of the measurement error is psented too