It is an important field to estimate stand average height using remote sensing technology. SAR interferometry （InSAR）technology uses the phase information of single look complex SAR data to get three-dimensional information of the earth surface. In recent years，this technology has been used widely. Having considered the advantages of InSAR and the characteristics of woodland，this paper focus mainly on using SAR interferometry technology to estimate average height of stand with SIR-C/ X-SAR L-band and C-band data. In this paper，after a brief review of InSAR technology and its major application fields，the principles of SAR interferometry are introduced. Then the methods of estimating stand height are given. At last，SIR-C/ X-SAR C-band and L-band SLC data of Daxing'anling are processed and the estimated stand height is calculated and analyzed with the field measurements. The result shows that it is potential for InSAR technology to estimate effective stand height. Several conclusions are drawn as follows：（i）It is potential for InSAR technology to estimate effective stand height. Stand height information can be acquired from the digital surface model（DSM）gained from complex SAR data. If the appearance of forests is very regular，the short wavelength SAR data can get better result. But if the appearance of forests is irregular，the more steady result can be obtained using long wavelength SAR data.（ii）Only the method of“differential height between stand and nearby”is useful now. Other methods，which require accurate GCPs during InSAR processing， were not useful in this study.（iii）Different wave band should be selected if the appearance of forests were different obviously. If the appearance of forests were better，the short wave such as X or C band should be selected. Otherwise，the long band such as P or L band should be selected.（iv）SAR interferometry technology can be used to monitor stand height increment. Because the effective tree height can be estimated，we can use InSAR data of multi-year interval to monitor tree height increment during this interval.