This article starts from the two basic principles of special relativity and, combined with spatial symmetry, provides a new detailed derivation process for the Lorentz transformation formula. Compared to the usual proofs in textbooks, this method utilizes spatial symmetry to clarify certain issues without introducing the concept of ‘interval.’ The paper carefully discusses the method for setting up coordinate systems and their impact on the transformation equations, demonstrating the reasons why the transformation formulas for x′ and t′ are independent of y and z, and why the transformation formulas for y′ and z′ are independent of x and t. These issues are not explained in standard textbooks. This proof process serves as a reference for students and teachers in learning or teaching university physics and physics majors.
