In this article, we examine the extent to which children with autism and children with learning difficulties can be discriminated from their responses to different patterns of sensory stimuli. Using an adapted version of the Short Sensory Profile (SSP), sensory processing was compared in 34 children with autism to 33 children with typical development and 22 children with learning difficulties without autism. Both clinical groups showed high symptoms of sensory impairment compared to controls. However, the autism group displayed higher levels of impairment in auditory hyper-sensitivity and visual stimulus-seeking factors compared to controls and the learning-disabled group. Using a discriminant analysis we found a combination of four factors which correctly classified 80.9% of the children. Implications for the diagnostic value of sensory processing in autism are discussed. (Contains 5 tables.)