This paper describes the microwave backscattering characteristics of three kinds of conifers, Matsu ( Japanese pine), Sugi (Japanese cedar) and Sawara (Japanese cypress), in the C and X bands for polarization combinations HH, VV, HV and VH. The measurements were made indoors using rotating-tree targets. ( i) Differences between HH and VV, (ii)the levels of the like backscatters of three conifers, and ( in) depolarization are discussed in relation to the features of canopy structure and leaf shapes. The method employed in this study will be ofuse in radar-signature studies of a wide variety of trees.