In the way to develop the educational system in Saudi Arabia, the emphasis was only on the materials with no more attention for the role of the learner and the teacher in the learning process or even the external factors around them. However, there are many theories and approaches that may help the Saudi students in different levels to understand the real aims of learning. Constructivism is one of the most influential theories in learning but not the only one. Constructivist approach has different versions that might be applied successfully in Saudi context. This article will introduce two versions of constructivism which are cognitive and social constructivism. This approach can make a real change in learners and teachers in the circle of learning process in Saudi Arabia. Constructivism will be presented as an effective theory of knowledge can improve the educational system of Saudi Arabia.