Previous studies on augmented reality (AR) book learning have not provided an in-depth examination of the learning process, especially the interaction involved in child–parent shared book reading. Choosing an AR picture book to introduce its artistic work, this study aimed to explore how children and parents read the book through a series of analyses of behavioral patterns and cognitive attainment. A total of 33 child–parent pairs voluntarily participated in this study. Based on the indicators of the child–parent reading behaviors generated through content analysis, four behavioral patterns of AR picture book reading were identified: parent as dominator, child as dominator, communicative child–parent pair, and low communicative child–parent pair. The relationships between the child–parent reading behaviors and the children's cognitive attainment were further identified. Specifically, the child–parent behaviors of “parent as dominator” and “low communicative child–parent pair” were likely associated with simple description of the appearance of the artistic work by the children (low-level cognitive attainment). Conversely, the “child as dominator” and “communicative child–parent pair” behaviors resulted in the children explaining the artistic work they had seen or using their imagination to describe the content of the book (high-level cognitive attainment).