Student engagement, consisting of behavioural, cognitive, and emotional components, has been proven to influence both academic success and psychological well-being. To examine the linkages among the three aspects of academic engagement, a sample of 789 Chinese primary school students (47% girls; 39% 3rd graders, 31% 4th graders, 30% 5th graders) completed the Mathematics Engagement Scale at three 6-month intervals over the course of 1.5 years. Results indicated that the effects of behavioural, cognitive, and emotional engagement amplified and influenced one another over time. Specifically, behavioural engagement stably predicted cognitive and emotional engagement over time, but the prediction of cognitive engagement on emotional engagement was not consistent from T1 to T2 and from T2 to T3. In addition, emotional engagement significantly predicted behavioural and cognitive engagement only from T2 to T3. These findings support academic engagement as multidimensional construct and advance the understanding of its internal dynamical and continuous developmental interrelations.