The purpose of this study was to find an effect of Metaphon Intervention on the improvement of speech intelligibility of preschool children with articulation-phonological disorders. Subjects were 4 preschool children with articulation-phonological disorders. A multiple baseline design across subjects was used to examine the effect of the program. The program consisted of 2 steps. The first step was composed of concept level, sound level, phoneme level, and word level. The second step was on sentence level. Results were as follows: First, metaphon ability of all subjects was improved after the Metaphon Intervention. Second, speech intelligibility of all subjects was improved after Metaphon Intervention. From the results above, Metaphon Intervention can be effective to improve not only phonological awareness and metaphon but also overall speech intelligibility of preschool children with articulation-phonological disorders.