All students are different in terms of their learning paces, levels of knowledge mastery and knowledge gaps. In the traditional human-teacher-centered instructional setting, however, students’ different learning needs are hard to be fulfilled because of the undifferentiated instructions and teachers’ divided attention on each of the student. The unequal educational resource distribution is also prevalent across the globe. High-quality education is not accessible to every student due to geographical constraints, limited resources, and it is often unaffordable for many families. Squirrel AI Learning developed an intelligent adaptive learning system which allows students to progress at their own paces. It precisely diagnoses students' knowledge weaknesses and assesses their learning situations at real time. It continuously adjusts learning contents and paths to maximise students’ learning efficiencies and outcomes. Squirrel AI Learning has set up over 2,400 learning centres across 600 different cities in China and nearly 2 million students have used its system. Squirrel AI’s intelligent adaptive learning system offers optimized learning solutions and synchronized tutoring support to maximize learning efficiency and effectiveness as well as to develop students’ learning capacity, methodology, and competencies. In this talk, the underlying AI techniques used to build the systems and the performance evaluation experiments will be introduced.