This research will attempt to expand existing insight and upgrade experiences of the Montessori pedagogy perspective and the application of Montessori materials in stimulating sensory integration, beacuse there are still no studies or research on this topic. The aim of this research was to evaluate the quantitative and qualitative effects of the aplication of Individualized program for stimulating sensory integration based on initial anassesment of sensory processing in children with autism spectrum disorder. The programme and the evaluation of the programe was based on the System for assasment of sensory integration dysfunction (Viola, 2002., transation and adaptation Fulgosi-Masnjak, R., Osmaničević, L. i Lang, M., 2004). The programm included the use of Montessori materials as well as some elements of Montessori pedagogy. Program was conducted for eight months at the Center for education „Velika Gorica“, after which a final evaluation was conducted. Quantitative analysis of data obtained by comparing the initial and final results, confirmed the hypothesis that Individualized program for stimulating sensory integration will positively affect on sensory processing in aimed areas. Results that are collected during the programme are showing progress in sensory procesing in proprioceptive and auditory sense as well as advances in the development of motor planning in a child with an autism spectrum disorder. The qualitative part of research was conducted through the participatory observation method through the analysis of videos and photos, analysis of reaserchers' diary and mother's diary that she wrote during the programme. The key findings of this research indicate the contribution of the program through demonstrating activities, identifying progress and recommendations in the area of the auditory, proprioceptive sensory sistem and encouraging the development of motor planning. In addition, there is also progress in other sensory sistem, as well as in the other areas, progress in collaboration, improved focus on materials or activities, improving attention and concentration, reducing challenging behavior.