This is a case review study of a 15-year-old Chinese boy diagnosed with Autism Spectrum Disorder (ASD) or autism (for short) when he was at 3 years old. The aim of this paper is to validate the boy’s autism diagnosis as well as his functional level of learning. Therefore, the author has chosen to use an eclectic diagnostic model based on (i) the hierarchy of the six building blocks of skills and abilities (Chia, 2008; 2012), and (ii) the process of cross-battery assessment (X-BA; Flanagan & McGrew, 1997) that involves conducting a series of standardized tests and checklists. The X-BA results show that despite making significant improvements in many areas of his development, the verbal comprehension, which is a language component, continues to pose as a big challenge for him. The challenges in using language and communicating have always been a salient feature in individuals with ASD (Dombrowski, 2015; Belkadi, 2006). With this piece of information based on the latest assessment results, the author has taken a step further in her attempt to validate JC’s autism diagnosis. This will certainly provide JC’s therapists and supporting educators a better sense as to how they should go about their respective intervention strategies to help him.