The usefulness of time domain reflectometry, TDR, for moisture of cereal grain was examined. TDR was applied to determine the moisture dependent relative dielectric constant, e, of the samples. A relationship between gravimetric moisture on wet basis, 6, and relative dielectric constant was investigated for wheat, rape, vetch, barley, Triticale and maize. Obtained results showed a linear 0(Ve) relationship, with intercept and slope varying from one species to another. Fitting a regression line to the 0(Ve) data set for each particular species resulted in a coefficient of regression R = 0.9959 and standard deviation SD = 0.0097 at best, and R = 0.9795 and SD = 0.0211 at worst case. Fitting the regression line to the aggregated 0(Vf) data set, comprising all species together, resulted in R = 0.9595 and SD = 0.0289. Thus, it was concluded that TDR could be a convenient technique to estimate the gravimetric moisture of grain with no specific calibration needed if readings of moderate accuracy were sufficient.