Abstract: Taken data of DEM (digital elevation model), CHM (canopy height model) obtained from Lidar and sample survey data as assisted data, the feasibility of forest height evaluation with TanDEMX data by DEM difference method based on interferometric elevation mensuration technique were analyzed in Puer test sites. The results showed that TanDEMX data have the potential capability in forest height assessments. With the support of high accurate DEM, the results could keep high coincidence with Lidar CHM, the RMSE of them was 439m and R2 was 070. Furthermore, the results also indicated that the phase noise dramatically affected the extraction accuracy of DSM and then affected the forest height assessment. Before elimination of phase noise, the R2 of the evaluation results and CHS was 023, but the value was 070 for the case that after phase noise correction.