We present a novel method for scalable and robust image transmission over ATM networks. The algorithm is based on a scalable set partitioning in hierarchical trees (SSPIHT) coding scheme, in which the encoded image bit streams for packeting and transmission are divided into a number of layers. By accumulating different numbers of layers in the decoder side, images with different resolutions and distortions can be reconstructed. Decoders having different capacities therefore can share the same encoder. In addition, these layers have different degrees of significance so that transmission errors in insignificant layers will not cause severe degradation in performance for image reconstruction. Finally, we describe three basic schemes for the transmission of SSPIHT-encoded cells over ATM channels. Simulation results show that the algorithm is effective for the applications where robust and scalable transmissions are desired.