Adopting differentiated teaching and learning strategies has proved effective in addressing students' diverse capabilities and potentials as well as developing their skills. This study examines the implications of differentiated instruction for self-actualization among high school students. For achieving this purpose, the quasi-experimental approach was adopted. The sample consisted of (58) high school students from Riyadh, Saudi Arabia. They were subdivided into an experimental group comprising (28) students taught in a differentiated classroom environment and a control one comprising (30) students taught in a traditional classroom environment. Two scales, a differentiated classroom environment scale and a self-actualization scale, were prepared and applied upon the participants. The results showed a high level of self-actualization among the experimental group students, indicating that differentiated instruction improved their self-actualization skills. Differentiated instruction provided students with an environment suitable to make them feel self-confident, establish positive relations with their classmates, and positively interact and cooperate with them. In the light of these results, the author recommends holding training courses and workshops to qualify teachers for designing and utilizing differentiated instruction.