ASD spectrometer was used to the study on the spectral reflectance of four kinds of sand-fixing plants Populus spp., Salix gordejevii, Caragana microphylla and Pinus sylvestris in Horqin sandyland under the controlled background reflectance noise, vegetation coverage and plant water content, and its ground spectral biomass models were analyzed by using NDVI and plant coverage and above ground biomass, respectively. The results showed that the trend of spectral reflection curves of four kinds of sand-fixed plant species was basically similar, but there were differences in wavelength of 620-670 nm and 841-876 nm. C. microphylla was one of the easiest plants to be distinguished in wavelength of 620-670 nm, following S. gordejevii and Populus spp., P. sylvestris and Populus spp. were easy to be distinguished in the wavelength of 841-876 nm. The relationship between NDVI and vegetation coverage and biomass was very close for the four, and the fitting precision of the models were highest. Compared with them, the models of NDVI-vegetation coverage were better than the NDVI-biomass because the differences of calculated results by the NDVI-coverage models were very smaller than the calculated results by the models of NDVI-biomass of these. However, the influence of dominant plant species should be paid more attention and conformed them involved in the quadrats sampling during remote sensing monitoring in regional vegetation productivity.