Purpose: To explore the impact of parent–child dialogic reading (DR) versus typical reading (TR) and artificial intelligence (AI)-assisted DR training on emotional regulation (ER) of children with attention-deficit hyperactivity disorder (ADHD) from low-to-middle-income families. Methods: This study recruited 249 children with ADHD from China and randomly assigned them to four groups: AI-DR, social worker-led DR, TR, and a control group. The intervention lasted 4 weeks, with pretests and posttests administered to assess ER via the Preschool Behavioral and Emotional Rating Scale and the coding of parent–child reading audio-recordings. Results: Parent–child storybook reading significantly improved ER in children with ADHD. In particular, the DR group had better ER development than the TR group. Furthermore, AI chatbots were equally effective as professional social workers in training parents on DR techniques. Conclusions: Parent–child storybook reading and AI-assisted training offer scalable, cost-effective strategies for ER interventions targeting children with ADHD.