In this paper a 3-D SAR imaging technique based on Compressive Sampling is experimented on ERS 1-2 data. The technique is based on the sparsity property of the image to be focused along the elevation direction (i.e. only few scatterers with different elevation are present in the same range-azimuth resolution cell), exploits a reduced number of unevenly spaced acquisitions and allows an increased elevation resolution. Numerical results on real data are compared with those obtained by using Truncated Singular Value Decomposition (TSVD) techniques.