Technical Abstract: Capacitance probe sensors are a popular electromagnetic method of measuring soil water content. However, there is concern about the influence of soil salinity on the sensor readings. In this study capacitance sensors are calibrated for a saline silty clay soil. The calibration procedure incorporates both the observed response of the sensors in the saline soil and the theoretical response of the sensors in non-lossy soil (no energy losses due to ionic conductivity or relaxation). The difference between the sensor frequency in non-lossy soil and saline soil as a function of ionic conductivity was described with S-shaped curves (r2 of 0.82 and 0.34 at two locations). Volumetric water content was calculated by correcting for the reduction in frequency that occurs when the sensor is used in saline soil. Measured and predicted volumetric water contents compared reasonably well (r2 = 0.86), although predicted volumetric water content was overestimated by about 15 percent at high water content.