A priori knowledge plays an important role in the retrieval of surface albedo from satellite observations.Here a BRDF archetype database is built according to Anisotropic Flat Index（AFX） which can identify surface reflectance anisotropy.Then a method to derive land surface albedo from spare observations and BRDF archetype is presented.Albedos from all the observations and full inversion method are used to validate the albedo estimation from our method.Compared results show that

when the observations that have view zenith angles less than 40° are not on the cross-principle plane can only represent part of reflectance anisotropy.Compared with full inversion method

the maximum absolute error of BRDF archetype inversion method is 0.036

and the relative error is improved about 5% —10%.For those observations are located on the cross-principle plane

the largest absolute difference of full inversion method is up to 0.18 due to the insufficient and spare angular samples.However

the BRDF archetype inversion method appears more accurate.In sum

BRDF archetype inversion method constrains BRDF shape over the entire space and was less dependent on the distribution of the observations.It was also less sensitive to noise.For the multi-angle data that have insufficient information

BRDF archetype method is preferred than full inversion method.